DaniWeb IT Discussion Community - C

Segmentaion fault while reading large file

sree2 — Tue, 01 Dec 2009 05:40:11 GMT

bobsced0$ gcc -g -o prog ss.c
bobsced0$ ./prog
File size is:906984
Segmentation fault
bobsced0$ gdb prog
GNU gdb 6.8
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-unknown-linux-gnu"...
(gdb) run
Starting program: /nfs/cluster/home/ncsi23/prog
File size is:906984

Program received signal SIGSEGV, Segmentation fault.
0x0000000000401449 in main (argc=1, argv=0x7fbfffedb8) at ss.c:45
45 while ((position=fgets(buffer,s, infile)) != NULL)
(gdb) print *position
$1 = 0 '\0'
(gdb) print position
$2 = 0x7fbfffed10 ""
(gdb)
Any one help me please. I'm trying to read a large file, i'm getting this error. i can read up to 2 lakh words from a file. but i can't read with more size. Could you help me how to use valgrind in PuTTy .

Question about format specifiers in C

fedya — Tue, 01 Dec 2009 03:10:20 GMT

Hello,

Can someone explain me what does this mean?

"40[^\"], %*c"

Thanks

My family Feud Game Error

asadc — Tue, 01 Dec 2009 00:38:29 GMT

This is my program

///////////////////////////////////////////////////////////////////////////////////

// ICS 3U1 - Mrs. Shanks

// Asad Choudhry

// November 28, 2009

// Family Feud

// 

// This program takes as input the question numbers, the questions, the answers,

// and the points. the question number is saved to the questionNumArray, the

// the question is saved to the questionNameArray, the answers are saved to 

// the answersArray and the points are saved to the answersNumArray.

// 

// This prgram will then and check if the user wants the rules, if yes the output 

// will be the rules. The loop will then generate a random question, and take as 

// input a guess from the user, the program will

// check if the guess is equal to one of the answers in answersArray, if so 

// the loop will add the points in answersNumArray to the score, add one to the

// correct answers, and add one to found, the output will be the points won and

// "Correct". the loop will then check if found is equal to 1 if not one is 

// added to strikes and the output is "Incorrect". The loop check if three 

// questions have been asked, if so the users final score is the output,

// otherwise, the next question is asked and the score is the output. The loop

// will check if the users score is greater then the highscore, if so the 

// output will be the players score to a file, and the the output to the screen

// will be "Congragulations you beat the highscore!" The loop will then check 

// if the user wants to play again, if so the loop repeats. Otherwise the 

// output will be "Thank-you for playing."

///////////////////////////////////////////////////////////////////////////////////

// Variables List:

// found = 0;

// count = 0;

// max = 0;

//int score = 0;

//int guess = 0;

//int repeat = 0;

//int errorCheck = 0;

//int correct = 0;

//int min = 0;

//int strikes = 0;

//int randomNum = 1;

//int highScore = 0;

//String playAgain = "";

//String name = "";

//String input = "";

//final int RANGE = 4;

//final int EMPTY = 0;

//final int MAX_INPUT = 34;

//final int GUESS_MAX = 8;

//final int MAX_CHECK = 7;

//final int ANSWERS_CORRECT = 5;

//final int MAX_QUESTION = 3;

//final int MAX_ARRAY = 35;

//final int NUM_RANGE = 7;



import java.io.*;

class FamilyFeud

{

  public static void main (String args [])

    throws java.io.IOException 

  {

    int found = 0;

    int count = 0;

    int max = 0;

    int score = 0;

    int guess = 0;

    int repeat = 0;

    int errorCheck = 0;

    int correct = 0;

    int min = 0;

    int strikes = 0;

    int randomNum = 1;

    int highScore = 0;

    String playAgain = "";

    String name = "";

    String input = "";

    final int RANGE = 4;

    final int EMPTY = 0;

    final int MAX_INPUT = 34;

    final int GUESS_MAX = 8;

    final int MAX_CHECK = 7;

    final int ANSWERS_CORRECT = 5;

    final int MAX_QUESTION = 3;

    final int MAX_ARRAY = 35;

    final int NUM_RANGE = 7;

    int random [] = new int [RANGE];

    int questionNumArray [] = new int [MAX_ARRAY];

    int answersNumArray [] = new int [MAX_ARRAY];

    String questionNameArray [] = new String [MAX_ARRAY];

    String answersArray [] = new String [MAX_ARRAY];

    

    

    // This loop will and check if the user wants the rules, if yes the output will

    // be the rules. The loop will then generate a random question, and take as 

    // input a guess from the user, the program will

    // check if the guess is equal to one of the answers in answersArray, if so 

    // the loop will add the points in answersNumArray to the score, add one to the

    // correct answers, and add one to found, the output will be the points won and

    // "Correct". the loop will then check if found is equal to 1 if not one is 

    // added to strikes and the output is "Incorrect". The loop check if three 

    // questions have been asked, if so the users final score is the output,

    // otherwise, the next question is asked and the score is the output. The loop

    // will check if the users score is greater then the highscore, if so the 

    // output will be the players score to a file, and the the output to the screen

    // will be "Congragulations you beat the highscore!" The loop will then check 

    // if the user wants to play again, if so the loop repeats. Otherwise the 

    // output will be "Thank-you for playing."

    do

    {

      FileReader fro = new FileReader ("survey.txt");

      BufferedReader bfr = new BufferedReader (fro);

      FileReader frt = new FileReader ("highScore.txt");

      BufferedReader bhr = new BufferedReader (frt);

      BufferedReader br = new BufferedReader (new InputStreamReader (System.in));

      

      

      

      

      // This loop takes as input the question numbers, the questions, the answers,

      // and the points. the question number is saved to the questionNumArray, the

      // the question is saved to the questionNameArray, the answers are saved to 

      // the answersArray and the points are saved to the answersNumArray.

      for (int countArray = 0; countArray <= MAX_INPUT; countArray ++)

      {

        input = bfr.readLine();

        questionNumArray [countArray] = Integer.parseInt (input);

        questionNameArray [countArray] =  bfr.readLine();

        answersArray [countArray] = bfr.readLine();

        input = bfr.readLine();

        answersNumArray [countArray] = Integer.parseInt (input);

      }

      fro.close();

      

      System.out.println ("Welcome to Family Feud PHS Version");

      input = bhr.readLine();

      highScore = Integer.parseInt (input);

      System.out.println ("The previous high score was: " + highScore);

      frt.close();

      System.out.println ("Can you beat it?");

      System.out.println ("What is your Name?");

      name = br.readLine();

      

      

      System.out.println ("Do you want the rules?");

      input = br.readLine ();

      

      // This selection checks if input equals "yes" if so the output is the rules.

      if (input.equalsIgnoreCase ("yes"))

      {

        System.out.println ("Now for the rules. A survey was given to one hundered" +

                            " people they each they each answered seven questio" +

                            "ns, the top five answers were taken. You will be as" +

                            "ked three of the questions, each question has five " +

                            "correct answers, each will have a point value assoc" +

                            "iated with it correspnding to how many people answe" +

                            "red it on the survey. The player will guess as to t" +

                            "he answer if correct the points the answer has will" +

                            "be added to the players score. After three incorrec" +

                            "t answers the question is over, after three questio" +

                            "n the players score is shown and the game is over.");

      }

      

      // This loop will generate a random question, and take as input a guess from 

      // the user, the program will check if the guess is equal to one of the answers

      // in answersArray, if so the loop will add the points in answersNumArray to 

      // the score, add one to the correct answers, and add one to found, the output 

      // will be the points won and "Correct". the loop will then check if found is

      // equal to 1 if not one is added to strikes and the output is "Incorrect". The

      // loop check if three questions have been asked, if so the users final score 

      // is the output, otherwise the next question is asked and the score is output.

      for (int countQuestion = 1; countQuestion <= MAX_QUESTION; countQuestion ++)

      {

        System.out.println ("\nRound: " + countQuestion);

        randomNum = (int)(Math.random() * NUM_RANGE);

        // This loop will take as input a guess from the user, the program will check

        // if the guess is equal to one of the answers in answersArray, if so the 

        // loop will add the points in answersNumArray to the score, add one to the 

        // correct answers, and add one to found, the output will be the points won 

        // and "Correct". the loop will then check if found is equal to 1 if not one

        // is added to strikes and the output is "Incorrect". The loop check if three

        // questions have been asked, if so the users final score is the output, 

        // otherwise, the next question is asked.

        while (strikes != MAX_QUESTION || correct != ANSWERS_CORRECT)

        {

          System.out.println (questionNameArray [randomNum * ANSWERS_CORRECT]);

          

          min = ANSWERS_CORRECT * randomNum;

          System.out.println ("What is your guess?");

          input = br.readLine ();        

          max = min + RANGE;

          

          // This loop will check if the guess is equal to one of the answers in 

          // answersArray, if so the loop will add the points in answersNumArray to

          // the score, add one to the correct answers, and add one to found, the 

          // output will be the points won and "Correct".

          for (int answerCheck = min; answerCheck <= max; answerCheck++)

          {

            // This Selection will check if the guess is equal to one of the answers

            // in answersArray, if so the loop will add the points in answersNumArray

            // to the score, add one to the correct answers, and add one to found, the 

            // output will be the points won and "Correct".

            if (input.equalsIgnoreCase (answersArray [answerCheck]))

            {

              score += answersNumArray [answerCheck];

              correct ++;

              System.out.print ("Correct!");

              System.out.println (" That was worth " + 

                                  answersNumArray [answerCheck] + " points.");

              answersArray [answerCheck] = null;

              count ++;

              found ++;

            }

          }

          // This selection will check if found is equal to 1, if not one is added to

          // strikes and the output is "Incorrect".

          if (found != 1)

          {

            System.out.println ("That was incorrect.");

            strikes ++;

          }

          

          // This selection will check if correct is equal to ANSWERS_CORRECT, if so

          // strikes will be equal to MAX_QUESTION, esle if strikes is equal to 

          // MAX_QUESTION, correct is will be equal to ANSWERS_CORRECT.

          if (correct == ANSWERS_CORRECT)

          {

            strikes = MAX_QUESTION;

          }

          else if (strikes == MAX_QUESTION)

          {

            correct = ANSWERS_CORRECT;

          }

          found = EMPTY;

        }

        correct = EMPTY;

        strikes = EMPTY;

        System.out.println ("Your score is " + score + ".");

      }

      // This selection will check if the players score is higher then the 

      // highscore, if so the output will be the players score to a file, and the

      // the output to the screen will be "Congragulations you beat the highscore!"

      if (score > highScore)

      {

        FileWriter fw = new FileWriter ("highScore.txt");

        fw.write (score + "\r\n");

        fw.close();

        System.out.println ("Congragulations you beat the highscore!");

      }

      System.out.println ("Would you like to play again?");

      input = br.readLine ();

    }

    while (input.equalsIgnoreCase ("yes"));

    System.out.println ("Thank-you for playing!");

  }

}

This is the survey.txt file

1

What is your favourite breakfast cereal?

Frosted Flakes

17

1

What is your favourite breakfast cereal?

Special k

16

1

What is your favourite breakfast cereal?

Cheerios

14

1

What is your favourite breakfast cereal?

Cinnamin Toast Crunch

8

2

What is your favourite subject in school?

Gym

26

2

What is your favourite subject in school?

Science

11

2

What is your favourite subject in school?

Math

8

2

What is your favourite subject in school?

Art

7

2

What college or university do you want to attend?

None

6

3

What college or university do you want to attend?

University of Toronto

21

3

What college or university do you want to attend?

None

15

3

What college or university do you want to attend?

Durham College

9

3

What college or university do you want to attend?

Harvard

5

3

What college or university do you want to attend?

University

5

4

What is your favourite colour?

Blue

42

4

What is your favourite colour?

Red

21

4

What is your favourite colour?

Green

11

4

What is your favourite colour?

Purple

10

4

What is your favourite colour?

Black

3

5

What is your favourite shakespeare play?

Romeo and Juliet

35

5



What is your favourite shakespeare play?

None

30

5

What is your favourite shakespeare play?

Macbeth

13

5

What is your favourite shakespeare play?

King Lear

4

5

What is your Favourite Shakespeare play?

Hamlet

4

6

What is your Favourite brand of potato chips?

Lays

50

6

What is your Favourite brand of potato chips?

Doritos

20

6

What is your Favourite brand of potato chips?

None

7

6

What is your Favourite brand of potato chips?

Miss Vickie's

7

6

What is your Favourite brand of potato chips?

Sunchips

5

7

What is your Favourite Car Company?

Ford

16

7

What is your Favourite Car Company?

Lamborghini

12

7

What is your Favourite Car Company?

Toyota

12

7

What is your Favourite Car Company?

BMW

9

7

What is your Favourite Car Company?

General Motors

5

This is the highscore file

I keep getting this error:
java.lang.NumberFormatException: For input string: "None"
at java.lang.NumberFormatException.forInputString(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at FamilyFeud.main(FamilyFeud.java:128)

I cant figure out the solution what so ever
Please and thank you :)

pls help segmentation fault error

dark1806 — Mon, 30 Nov 2009 22:46:04 GMT

hi..pls help me with this ...when i run this c program i get in result segmentation fault message (i run in ubuntu terminal):

#include

#include

int main()  {

       char *s,*c;

       struct utmp *u;

       int i;

       c=getlogin();

       setutent();

       u=getutent();

       while(u!=NULL)  {

          if(u->ut_type==7 && strcmp(u->ut_user,c)==0) {

               printf("%-12s",u->ut_user);

               printf("%-9s",u->ut_line);

               s=ctime(&u->ut_time);

               for(i=4;i<16;i++)

               printf("%c",s[i]);

               printf("(%s",u->ut_host);

               printf(") ");

          }

       u=getutent();

       }

}

and when compile i get warnings:
gcc -o who who.c
who.c: In function ‘main’:
who.c:7: warning: assignment makes pointer from integer without a cast
who.c:14: warning: assignment makes pointer from integer without a cast

i must mention that programs must return the same as the command who (linux)
thx...and sry for bad english

need urgent help

myheart — Mon, 30 Nov 2009 22:31:43 GMT

can anyone help me doing my simple assignment,please.
I feel fed up and got confused so far

Program for network Scan

Shaikh Mohsin — Mon, 30 Nov 2009 20:30:19 GMT

Hello Friends,
I want to writ a program which scan network for Operating system at boot time.plz if any known how to start writing that program in c.reference plz
Thank u all

Problem when trying to read a bitmap file

adraganov — Mon, 30 Nov 2009 20:10:25 GMT

Hi, guys. I've been reading your forum for some time.
Now I need a little help again.
I am trying to read a bitmap file using BITMAPFILEHEADER, BITMAPINFOHEADER and RGBQUAD in windows.h - I need RGB values or only one of them. All the info in header structures is OK. My file has no compression(I drew 4 pixels with paint).

void ReadBitmap(char* FileName)

{ 

        RGBQUAD Palette[4];



        BITMAPFILEHEADER bitmapFileHeader;

        BITMAPINFOHEADER bitmapInfoHeader;

        FILE *stream=fopen(FileName,"rb");

        if(stream ==NULL)

                printf("ERROR: Can’t open “<
        else

        { 

                if((fread(&bitmapFileHeader,sizeof(BITMAPFILEHEADER),1,stream)) == -1)

                  printf("ERROR: Can’t Read Fileheader Stucture!”;");



                if ((fread(&bitmapInfoHeader, sizeof(BITMAPINFOHEADER), 1, stream) == -1))

                  printf("ERROR: Can’t Read Infoheader Stucture!”;");         

        }



        printf("compr - %d\n", bitmapInfoHeader.biCompression);

        printf("width - %d\n", bitmapInfoHeader.biWidth);

        printf("height - %d\n", bitmapInfoHeader.biHeight);



        RGBQUAD pixel;

        for(int l=0;l<4;l++)

          {

                  if((fread(&pixel,sizeof(RGBQUAD),1,stream))==-1)

                        {printf("<<“ERROR: Can’t read bitmap’s color palette!”;"); }

                   else

                          {

                                printf("/r - %d",int(pixel.rgbRed));

                                printf("/g - %d",int(pixel.rgbGreen));

                                printf("/b - %d",int(pixel.rgbBlue));

                                printf("/off - %d\n", pixel.rgbReserved); 

                           }

                }

I got following result

compr - 0

width - 4

height - 1

/r - 237/g - 28/b - 36/off - 36

/r - 21/g - 237/b - 28/off - 0

/r - 228/g - 176/b - 136/off - 239

/r - 228/g - 176/b - 136/off - 239

RGB values for the first pixel are OK, but then I got something in rgbReserved when it should be 0. The next values(including reserved) are mixed rgb values for the next 3 pixels.
if I understand bitmap file format correctly, the result should be something like this :

/r - 237/g - 28/b - 36/off - 0

/r - 237/g - 28/b - 36/off - 0

/r - 136/g - 0/b - 21/off - 0

/r - 239/g - 228/b - 176/off - 0

Can you tell me where I am wrong?

[Beginner] struct + dynamic memory allocation + free ()

gianx80 — Mon, 30 Nov 2009 15:10:47 GMT

Hi,
I'm studying the basis of C, C++ and Assembly languages at my university (I have two exams about these subjects,

for now) ... and I have a problem ^^.
I wrote a program in C (not so optimized, this isn't our present goal for my professors) that recieves in input an

integer (matrix size) and a double pointer to a square matrix and print on screen the co-ordinate of each square

sub-matrix from size 2 to n - 1 size (where n is the integer that my function recieves in input) that has inside

the biggest sum of its own members and the sum itself.
Then I modified the program so I created a struct in which I dynamically allocated two arrays in which i store the

co-ordinate that my function finds. So I can allocate them, I can populate themm I can access their elements but I

can't free them (I recieve an error regarding the corruption of the heap).
I can't figure out the problem ... I can dynamically allocate the matrix and free it, why I can't free my two

arrays?

#include 

#include 

#include 



typedef struct cont_

{

        int *datax;

        int *datay;

} cont;



int** mtx_a (int num);

int mtx_i (int num, int **mtx);

void mtx_p (int num, int **mtx);

int mtx_c (int num, int **mtx, cont data);

void mtx_d(int num, int **mtx);



cont mtx_sa (int num);

int mtx_ss (int num, int x, int y, cont data);

void mtx_sd (cont data);



int main ()

{

        // (1) Dichiaro le variabili.

        int num = 0;

        int check = 0;

        

        // (2) Chiedo all'utente di inserire il lato della matrice.

        do

        {

                printf("Inserire la lunghezza del lato della matrice quadrata: ");

                scanf("%d", &num);



                if (num <= 0)

                        printf("Il numero deve essere maggiore di 0\n");



        } while (num <= 0);



        // (I) Store Allocation

        cont data = mtx_sa (num);



        // (3) Dichiaro dopppio puntatore ed alloco spazio per matrice.

        int **test = mtx_a (num);



        // (4) Inizializzo matrice.

        mtx_i (num, test);



        // (5) Stampo la matrice.

        mtx_p (num, test);



        // (6) Eseguo operazioni su sotto-matrici quadrate.

        mtx_c (num, test, data);



        int i = 0;

        for (i = 2; i < num; i++)

        {

                printf("%d # %d\n", data.datax [i], data.datay [i]);

        }



        // (III) Store 3

        mtx_sd (data);

        

        // (7) Libero lo spazio allocato dinamicamente per la matrice.

        mtx_d (num, test);



        // (9) Metto in pausa l'applicazione per verificare i risultati e ritorno.

        system ("pause");

        return 0;

}



int** mtx_a (int num)

{

        int i  = 0;

        int j = 0;

        

        int **tmp = (int **) calloc (num, sizeof (int *));

        for (i = 0; i < num; i++)

        {

                tmp[i] = (int *) malloc (num * sizeof (int));

        }

        

        return tmp;

}



int mtx_i (int num, int **mtx)

{

        int i = 0;

        int j = 0;

        int val = 0;



        srand ((unsigned) time (NULL));



        for (i = 0; i < num; i++)

        {

                for ( j = 0; j < num; j++)

                {

                        mtx [i][j] = val;

                        val = (val + j + rand ()) % 9;

                }

        }

        

        return 0;

}



void mtx_p (int num, int **mtx)

{

        int i = 0;

        int j = 0;



        for (i = 0; i < num; i++)

        {

                for (j = 0; j < num; j++)

                {

                        printf("%d", mtx [i][j]);

                        

                        if (j == num - 1)

                                printf("\n");

                        else

                                printf(" ");

                }

        }

        printf("\n");

        

        return;

}



int mtx_c (int num, int **mtx, cont data)

{

        int i = 0;

        int j = 0;

        int z = 0;

        

        int side = num - 1;

        int lap = side * side;

        int sommaT = 0;

        int sommaD = 0;

        int I = 0;

        int J = 0;

        int lato = 2;

        int dis = 1;

        int pos1D = 0;

        int pos2D = 0;



        do

        {        

                for (z = lap; z > 0; z--)

                {

                        for (i = I; i <= I + dis; i++)

                        {

                                for (j = J; j <= J + dis ; j++)

                                {

                                        sommaT = sommaT + mtx [i][j];

                                }

                        }

                        

                        if (sommaT > sommaD)

                        {

                                sommaD = sommaT;

                                pos1D = I;

                                pos2D = J;

                        }



                        J++;



                        if (J >= side)

                        {

                                I = I++;

                                J = 0;

                        }



                        sommaT = 0;

                }



                // Store 2

                mtx_ss ((num + 1) - side, pos1D, pos2D, data);



                printf("Lato: %d # Somma sotto-matrice qudarata: %d. Coord. x: %d # y: %d\n\n", ((num + 1) - side), 



sommaD, pos1D, pos2D);



                side--;

                lap = side * side;

                lato++;

                sommaD = 0;

                I = 0;

                J = 0;

                dis++;

                        

        } while (side >= 2);



        return 0;

}



void mtx_d(int num, int **mtx)

{

        int i = 0;



        for (i = 0; i < num; i++)

        {

                free (mtx [i]);

        }

        free (mtx);



        return;

}



cont mtx_sa (int num)

{

        cont data;



        data.datax = (int *) calloc (num + 1, sizeof (int));

        data.datay = (int *) calloc (num + 1, sizeof (int));



        data.datax [0] = 0;

        data.datay [0] = 0;

        data.datax [1] = 0;

        data.datay [1] = 0;

        data.datax [num] = 0;

        data.datay [num] = 0;

        data.datax [num + 1] = 0;

        data.datay [num + 1] = 0;

        

        return data;

}



int mtx_ss (int num, int x, int y, cont data)

{

        data.datax [num] = x;

        data.datay [num] = y;

        

        return 0;

}



void mtx_sd (cont data)

{        

        free (data.datax);

        free (data.datay);



        return;

}

random number is not reused

raigs — Mon, 30 Nov 2009 13:27:11 GMT

I need to generate and reuse a 5 digit random number every time my program is executed. But the following generates random numbers every time the function is called.

#include 

#include 

#include 

#include 

#include 

#include 



int RANDOM(void)

{

        int RANDOMNUMBER = 0;



        srand((unsigned int)time(NULL));

        RANDOMNUMBER = rand() % 99999; // create a random 5 digit number to be reused in other functions



        if (RANDOMNUMBER < 10000)

        {

                RANDOMNUMBER = RANDOMNUMBER + 10000; // correction because sometimes the number generated is 4 digits long

        }



        return RANDOMNUMBER;

}



char *ONE(void)

{

        static char ONE1[15] = "";



        sprintf(ONE1, "ONE%.5i", RANDOM());



        return ONE1;

}



char *TWO(void)

{

        static char TWO2[15] = "";



        sprintf(TWO2, "TWO%.5i", RANDOM());



        return TWO2;

}



void THREE(void)

{

        printf("THREE%.5i\n", RANDOM());

}



int main(void)

{

/* A different random number is output every second. This is a problem because the program takes various seconds to execute. How can I reuse a random number every time the program is executed ? */



        puts(ONE());

        sleep(1);

        puts(ONE());

        sleep(1);

        puts(ONE());

        sleep(1);

        puts(TWO());

        sleep(1);

        puts(TWO());

        sleep(1);

        puts(TWO());

        sleep(1);

        THREE();

        sleep(1);

        THREE();

        sleep(1);

        THREE();



        return 0;

}

prime factors

poornimashobana — Mon, 30 Nov 2009 12:24:23 GMT

hi ,
anybody would help me how to print prime factors in c using recursive function

just wondering how this was done ?

Iam3R — Mon, 30 Nov 2009 12:19:02 GMT

The Programming languages started with the low level language( 1's and zero's , so no conversion is needed.

Assembly language is used mnemonics ( ADD,INC,DEC) so needs conversions as the machine cannot understand it directly.
there comes the Assembler.

Now the question is how the Assember was implemented, i mean which language?

soon compilers came in to picture.
how they are written i mean using which language?

i read, c compiler was wirtten in C itself .

then how it was compiled.

Thanks,
danian.

match two string with wildcards help

meghs007 — Mon, 30 Nov 2009 10:00:27 GMT

1. command line program for match two string and also allow the character
• * -- any number of character
• ? – Single Character
Ex.: I/p:- This is a string
Th?s is *g
O/p Both string are Same

pls help me to solve this program in c

[linked lists] Initialization doubly linked lists

tzushky — Mon, 30 Nov 2009 09:41:02 GMT

Good morning coders !,

I stumbled accross an initialization this morning and even though I get it , it's not 100%. I'll simplify it this way:

I have an array declaration:

uint8_t  MyArray[MAX_SIZE]

I have a linked list structure:

struct MyLL{

  struct MyLL  * next;

  struct MyLL * previous;

  uint16_t  whatever;}

and two globals :

MyLL * FirstBlock;

MyLL * LastBlock;

And then using these in an initialization function this way:

void MyInitFunc(void)

{

    MyLL     * first;

    MyLL     * last;

    uint8_t * mystart;

    uint8_t * myend;



    FirstBlock = NULL;

    LastBlock = NULL;



    mystart = &MyArray[0];

    myend   = &MyArray[MAX_SIZE];



    first = (MyLL *) mystart;

    last = (MyLL *) myend;

    last--;



    first-> whatever= init_whatever;

    first->next         = last;

    first-> previous  = NULL;



    last-> whatever = init_whatever;

    last->next          = NULL;

    last-> previous  = first;



    FirstBlock = first;

    LastBlock =last;

}

Why is that array so useful? Is it a sort of method to save up space for consecutive linked list pointers ?

I could really sue your help because the moment I thought linked lists were clear , this is shaking my confidence...

Thanks in advance,

T

Sort while creating the linked list

fedya — Mon, 30 Nov 2009 04:09:13 GMT

Hello guys! I have an assignment in my data structure class and I want to ask following thing:

I have txt file which is unordered (not sorted) say like this:

red apple
blue sky
white car
handsome boy
hello world

My program should read file into linked list and sort it while reading? for example: it should read first line "red apple" and place it in first order, then it has to read second line "blue sky" and place it in right order that is before "red apple" (alphabetically blue is upper then red). Next lines has to be ordered in this way.

I know how to make linked list. But i don't know how to sort it while reading text file

Note: I can easily apply some sorting algorithm after reading all content of file. But the main point of assignment is that I cannot use any sorting techniques(algorithms) here.

I nearly know sequence how to make. But i'm very weak at coding. So please can anyone help to me to code following sequence?



//get item

//check it with the head of the list

//if it's "before" alphabetically

   //make it the new head and the head its next value

//else

  //iterate through the list performing the same check as above

  //insert when appropriate

//repeat

Anyone can help me to make it?

Thanks in advance

Program Help Please!!

kat_stephens — Mon, 30 Nov 2009 03:18:45 GMT

I've started on an assignment and just can't get it right PLEASE help! The assignment is :Write a program that will do the following:

1.) Continuously prompt the user for words and store the words in a linked list.

Do not use an array or in any way pre-allocate any memory.

Use malloc() to request memory for each word as it is read.

2.) After the user has completed entering words, print the words in the

order that they were entered by the user. Then print them in the

reverse order from which they were entered.

After each word is printed in reverse, delete it from the linked list.

After the word is deleted, return the memory using free().

When the program ends the list should be empty.

Your program should allow for the possible storage of any number of words. Each word should allow a maximum size of 15 letters. Your program should make certain that this word length is not exceeded so that the program does not crash if longer words are entered by the user. Any word entered that is more than 15 letters should be discarded.

A sample run is shown below.

Sample Run

Enter a word: four

Do you have more words? yes or no: y

Enter a word: score

Do you have more words? yes or no: y

Enter a word: and

Do you have more words? yes or no: y

Enter a word: thiswordismuchtoobig

Do you have more words? yes or no: y

Enter a word: seven

Do you have more words? yes or no: y

Enter a word: years

Do you have more words? yes or no: y

Enter a word: ago

Do you have more words? yes or no: n

four

score

and

seven

years

ago

ago

years

seven

and

score

four

This is the code that I have now:

#include 

#include 

#define BIG 999

#define MAX 16



char getWord(char *word);



int main(void)

{

  char *tmpPtr=NULL;

  char *prevPtr=NULL;

  char *newPtr=NULL;

  char temp[MAX];

  

  struct node

  {

     char word[MAX];

     struct node *next;

  };

  

  struct node *list; /*list will point to the first node in the list*/

  

  /*Putting the first word in the list*/

  getWord(temp);

  list = (struct node *)malloc(sizeof(struct node));

  strcpy(list->word, temp);

  list->next = NULL;

  

  /*Getting the other words*/

  getWord(temp);

  newPtr = (struct node *)malloc(sizeof(struct node)); /*get the memory*/

  strcpy(newPtr->word, temp); /*load the node*/

  newPtr->next = NULL;

  

  /*Place the word in it's respective sorted position*/

  tmpPtr = list;

  prevPtr = NULL;

  while(strcmp(newPtr->word, tmpPtr->word) > 0)

  {

     prevPtr = tmpPtr;

     tmpPtr = tmpPtr->next;

     if(tmpPtr==NULL) /*End of the line*/

        break;

  }

  

  /*Insert the new node in sorted order*/

  if(tmpPtr==NULL)

  {    /*node goes at the end of the list*/

     prevPtr->next = newPtr;/*link new node to the current last node*/

  }

  else

     if(prevPtr==NULL)

     {    /*node goes at the front of the list*/    

        newPtr->next=tmpPtr;/*link new node to previous firs tnode*/

        list = newPtr;/*link list pointer to new node*/

     }

  else

  {   /*node goes before tmpPtr*/

      prevPtr->next=newPtr; /*link previous node to the new node*/

      newPtr->next=tmpPtr; /*link new node to next node*/

  }

  

  free(tmpPtr); /*tmpPtr is no longer need*/

  system("PAUSE");        

  return 0;

}





char getWord(char *word)

{

  char get[BIG];

  scanf("%s", get);

  while(strlen(get) !< MAX)

     printf("Error: Word is too long!");

     scanf("%s", get);

}

help translate this bash script into c code

hookah — Sun, 29 Nov 2009 22:07:51 GMT

Write a multi-module C program to manage an auto-parts database for a manufactory.
help translate the bash script into c

Quote:

#! /bin/sh
#Project 2 CSC 3320
#echo menu test program
stop=0 # reset loop termination flag.
while test $stop -eq 0 # loop until done.
do
cat << ENDOFMENU # display menu.
Main Menu
(e) Edit Submenu
(r) Report Submenu
(q) Quit
ENDOFMENU
echo -n 'your choice?' # prompt.
read reply # read response.
echo
case $reply in # process response.
"e")
echo "Edit Submenu:"
./EditSubmenu.sh # go to Edit submenu
;;
"r")
echo "Report Submenu:"
./ReportSubmenu.sh # go to report submenu
;;
"q")
stop=1 # set loop termination flag.
;;
*) # default.
echo illegal choice # error.
;;
esac
done

#!/bin/sh
#Project1 add submenu
echo -n "Name:" #use if here to make sure the part is not there
read name
echo -n "Operator's Name:"
read operator
echo ${name}:in:$date:${operator} >> part.txt
echo "A new auto part is added into your data book."

#!/bin/sh
#Project1 delete submenu
echo -n "Name:"
read name
sed "/^${name}:/d" part.txt > parttemp.txt
cp parttemp.txt part.txt
rm parttemp.txt
echo "$name is removed from your part database."

#!/bin/sh
#project1 display submenu
echo -n "Name:"
read name
egrep -i "^$name" part.txt | awk -F: -f display.awk

#!/bin/sh
#project1 return submenu
echo -n "Name:"
read name
grep -i "$name" part.txt | sed s/out/in/g part.txt

[asahib1@qubit ~]$ vi checkout.sh
#!/bin/sh
#project 1 checkout part submenu
echo -n "Name:"
read name
echo -n "Borrower's name:"
read borrower
borrower=$borrower
egrep -i "$name" part.txt | sed s/in/out/g part.txt

{
printf "%s:%s:%s:%s:%s\n\n", $1,$2,$3,$4,$5;
}

#!/bin/sh
#echo submenu test program
stop=0 # reset loop termination flag.
while test $stop -eq 0 # loop until done.
do
cat << ENDOFSUBMENU # display menu.
Edit Submenu
(a) Add an auto part
(p) Display an auto part
(i) Return an auto part
(o) Check an auto part
(d) Delete an auto part
(q) Return to main Menu
ENDOFSUBMENU
echo -n 'your choice?' # prompt.
read reply # read response.
echo
case $reply in # process response.
"a")
echo "Add an auto part:"
./add.sh # go to add submenu
;;
"p")
echo "Display an auto part:"
./display.sh # go to display submenu
;;
"i")
echo "Return an auto part:"
./return.sh # go to return submenu
;;
"o")
echo "Check an auto part:"
./checkout.sh # go to check submenu
;;
"d")
echo "Delete an auto part:"
./delete.sh # go to delete submenu
;;
"q")
stop=1
# go to Main menu
;;
*) # default.
echo illegal choice # error.
;;
esac
done

#! /bin/sh
# menu test program
stop=0 # reset loop termination flag.
while test $stop -eq 0 # loop until done.
do
cat << ENDOFMENU # display menu.
Report Submenu:
(n) Sort by Name
(o) Sort by Operator's name
(s) Sort by Status
(q) Return to Main Menu
ENDOFMENU
echo -n 'your choice?' # prompt.
read reply # read response.
echo
case $reply in # process response.
"n")
sort -t: +0 -1 part.txt | awk -F: -f display.awk
;;
"o")
sort -t: +1 -2 part.txt | awk -F: -f display.awk
;;
"s")
sort -t: +2 -3 part.txt | awk -F: -f display.awk
;;
"q")
stop=1 # set loop termination flag.
;;
*) # default.
echo illegal choice # error.
;;
esac
done

buffer a function?

raigs — Sun, 29 Nov 2009 22:06:43 GMT

N00B here. I need to reuse a function's return in other functions. The problem is that the function's return changes every time it is called. How to achieve this?

int FUNCTION1(void)

{

        // do stuff



        return FUNCTIONRESULT; // return to be reused in other functions

}



int FUNCTION2(void) // <- this must be void

{

        // do stuff

        int NUMBER = FUNCTION1(); // FUNCTION1's return is reused here but it is not the same value as in FUNCTION3



        return WHATEVER;

}



int FUNCTION3(void) // <- this must be void

{

        // do stuff

        int NUMBER = FUNCTION1(); // FUNCTION1's return is reused here but it is not the same value as in FUNCTION2



        return WHATEVER;

}

memset is behaving unexpectedly

johndoe444 — Sun, 29 Nov 2009 20:38:07 GMT

Hi,

This is the code fragment:

#include 

#include 

#include 

#include 



int main()

{

        int* bugs_bunny;

        bugs_bunny = (int*)malloc(3*sizeof(int));

        memset(bugs_bunny, 5, 3*sizeof(int));

        printf("bugs_bunny[0] %d\n",bugs_bunny[0]);

        bugs_bunny[0] = 17;

        printf("bugs_bunny[0] %d\n",bugs_bunny[0]);

        return (1);

}

The outcome is:

bugs_bunny[0] 84215045

bugs_bunny[0] 17

Why is the value printed for bugs_bunny[0] using memset producing garbage value while the 2nd one is printing the right result?

Thanks.

Problems with file I/O. Trying to read from .csv file

Mattpd — Sat, 28 Nov 2009 21:23:11 GMT

My file contains:

Hook,Mark,In, , ,Tire,Matt,Out,01/01/2001,Mike

My structure:

struct part {

  char name   [NAME_LEN+1];

  char owner  [OWNER_LEN+1];

  char status [STATUS_LEN+1];

  char date   [DATE_LEN+1];

  char renter [RENTER_LEN+1];

} parts [MAX_PARTS], temp [1];

And the code:

FILE *fp;

fp=fopen("parts.csv","r");

printf("%d", fp);                   //Added this for debugging

char buf[100];

int i;

for(i=0; i < MAX_PARTS; i++) {

  while(i<100 && fgets(buf,sizeof(buf),fp) != NULL){

    printf("%s", buf);          //for debugging

    strcpy(parts[i].name, strtok(buf,","));

    strcpy(parts[i].owner, strtok(NULL,","));

    strcpy(parts[i].status, strtok(NULL,","));

    strcpy(parts[i].date, strtok(NULL,","));

    strcpy(parts[i].renter, strtok(NULL,","));

    }

}

In this example, I am trying to save "Hook" into parts[0].name, "Mark" to parts[0].owner, "In" into parts[0].status, and then blank strings in parts[0].date and parts[0].renter. Then i++, so it should save "Tire" into parts[1].name, "Matt" into parts[1].owner, etc. Once the end of the file is reached, the loop should exit and it should continue with whatever code follows it. When I print fp, it is not null so it is opening, and when I print buf, it prints my file contents, so up to that point it is working. But if I try to print parts[0] or part[1] they are both blank. Why is nothing being copied?

calling function corrupts data

Vitriolics — Sat, 28 Nov 2009 18:37:33 GMT

Hey,

I have a program that it supposed to read two columns of data and then perform a calculation on them. The problem is reading the data in from the file. I have a function to count the lines, this works correctly. It returns it's value into a variable called lines.

The program then tries to read data from the file into some dynamically allocated memory. It then prints the results.

However sometimes the data read from the file is absolute junk.

The thing is that the data is never junk if i don't call the function "countlines" and just assign the variable lines the length of the dat file.

WIERD

#include 

#include 



int countlines(FILE* fp)

{

    int lines;

    char c;

    lines=0;

    

     while(c!=EOF)

      {

          c=getc(fp);

          

          

          if(c=='\n')

             lines++;

             

      }



      return lines;



}





    



int main(int argc, char *argv[])

{

  FILE* fp;

  int lines,i;

  float* x;

  float* fx;

  

  lines=3;

  

  

  fp=fopen("a.dat","r");

  

  

  if(fp==NULL)

  {

      printf("Error opening file\n");

      getchar();

      return 0;

  }

  

 lines=countlines(fp);   ////HERE IS THE DEMON  if i don't call this

                                        //the program gives expected output

                                        ///otherwise junk e.g all 0 or really big

                                       //numbers

  

  

      

  fx =(float*)malloc(lines*sizeof(float));

    x=(float*)malloc(lines*sizeof(float));

      

  if( fx==NULL)

  {

      printf("Error allocating memory\n");

      getchar();

      return 0;

  }

  

  

  if( x==NULL)

  {

      printf("Error allocating memory\n");

      getchar();

      return 0;

  }

  

  for(i=0; i
  fscanf(fp,"%f %f",&x[i],&fx[i]);

  

  

  for(i=0; i
  printf("%f %f\n",x[i],fx[i]);

  

 

 

  

  

  

  

  free(x);

  free(fx);

  

  fclose(fp);

  

  getchar();

  return 0;

}

I would really appreciate someone telling what i am doing wrong

thanks very much

oh and i'm compiling under dev c++ configured as C only

Find closest point from an array of points?

AndrewYY — Sat, 28 Nov 2009 15:58:49 GMT

I've got a large array of coordinates (a struct containing x and y, among other things) and for each pair of coordinates, I'm trying to find another pair that's closest to it from that array.

int i, j, d = 0, cd = 0, closest;

for(i=0;i
  closest = 0;

  for(j=0;j
    if (i != j){

      //find distance bewteen i and j

      cd = sqrt(pow(coords[i].x-coords[j].x,2)+pow(coords[i].y-coords[j].y,2))

      if(cd < d){

        d = cd;

        closest = j;

      }

    }

  }

  //do stuff with the 'closest' variable

}

The problem is, this code runs really slowly, as it has to execute size^2 times, and I'm constantly running this code because the x and y coordinates are always changing.

Is there a faster way to do what I'm trying to do? I know that I could potentially cut calculation time by 2, because if a is closest to b, then b is closest to a, but beyond that, I can't think of any optimizations.

loan amortization help in c program

schicksalf — Sat, 28 Nov 2009 10:35:58 GMT

Hello I need help to write a c program that prints a laon amortization schedule when user imputs, principal, annual percentage rate of interest, number of years to pay off the loan and monthly payment.
original loan amount=10,000
number of payments is 36
APR is 7.50
payment is 311.06
monthly payment=(rate+(((rate/1+rate)months)-1)*principal)
at the end of the loan..there should be a summary information of the total amount paid total interest paid and total principal paid
rate= annual percentage rate/1200
at the end of each month the amount of interest due on the loan is rate*principal_remaining

Trying to sort a structure

Mattpd — Sat, 28 Nov 2009 06:57:11 GMT

My attempt of a "bubble sort" only partially works. Say for example if this is my structure declaration:

struct part {

  char name   [NAME_LEN+1];

  char owner  [OWNER_LEN+1];

  char status [STATUS_LEN+1];

  char date   [DATE_LEN+1];

  char renter [RENTER_LEN+1];

} parts [MAX_PARTS], temp [1];

and the following code print:

Piston:Mike:In::
Hook:Mark:In::
Door:Kim:In::
Axel:Matt:In::

 for(i=0; i < num_parts; i++)

        printf("%s:%s:%s:%s:%s\n", parts[i].name, parts[i].owner, parts[i].status, parts[i].date, parts[i].renter);

My desired final output would be sorted alphabetically by the first field like this:

Axel:Matt:In::
Door:Kim:In::
Hook:Mark:in::
Piston:Mike:In::

The following code is my attempt at sorting, but instead of my desired output I get:

::::
Axel:Matt:In::
Door:Kim:In::
Hook:Mark:In::

void status (void){

 

  int i;

  int n;

  for (n=0; n < num_parts; n++){

  

  for (i=0; i < num_parts; i++)

        if (strcmp(parts[i].name, parts[i+1].name) > 0) {

          temp[1]=parts[i];

          parts[i]=parts[i+1];

          parts[i+1]=temp[1];

          

}

printf("\n");

}

  for(i=0; i < num_parts; i++)

        printf("%s:%s:%s:%s:%s\n", parts[i].name, parts[i].owner, parts[i].status, parts[i].date, parts[i].renter);

        

}

From what I can see the sorting is working correctly, except that for the first time the if() statement is iterated, there is something going wrong. In this example, in the first iteration Piston (parts[0].name) and Hook (parts[1].name) are compared. They need to be switched so they are but there is a problem when the Piston line is saved to temp, I think it is being saved saved with blank fields. After this first iteration, it seems everything is working correctly, so I end up with close to what I want, but in the end parts[0] is just a bunch of blanks.

A simpler example is, if the original order is:

Hook:Matt:In::
Door:Mike:In::

the output this code gives is:

::::
Hook:Matt:In::

Can you spot my mistake?

GTP header

omar isaid — Sat, 28 Nov 2009 00:50:16 GMT

Any one has an idea how to develop Header of GPRS tunneling protocol using C language or even has interest in something like that
I am a professional C/C++ programmers living in jordan

"suspicious pointer conversion" error

Ahmed Helmy — Fri, 27 Nov 2009 22:42:16 GMT

Dear all,
I practice a program about "stack by linked list" and I found this error "suspicious pointer conversion" in the part of defining "push" and "pull" function.

Thank you in advance.
Ahmed Helmy
ITI student.

starting out with a linked list

ganmo — Fri, 27 Nov 2009 19:59:22 GMT

Hey, I am currently following a code skeleton to implement the missing code for some function. Below is only some part of the implementation I've done so far. Yes it is not much yet...
I got stuck for the implementation of the list_add() function.

What I want to do there is to create a new node, and allocate some memory to it so I afterward can insert values to it. However I get compilation error. I have trial error it for awhile now without founding any solution. So I hoped for if someone know what error it is.

The error I get is

Quote:

error: invalid conversion from `void*' to `my_list*'

#include 



using namespace std;



struct list_item

{

    int key;                // identifies the data

    double value;           // the data stored

    struct list_item* next; // a pointer to the next data

};



struct my_list

{

    struct list_item* first; // a pointer to the first element of the list

};



void list_init(struct my_list* my_this)

{

    my_this = NULL;

}



void list_add(struct my_list* my_this, int key, double value)

{

    my_list *new_node;

        

        //allocate memory for next node

    new_node = malloc(sizeof(my_list));

}



int main()

{

        my_list a;

        list_init(a);

        

        return 0;

}

factorial

onruli — Fri, 27 Nov 2009 15:26:25 GMT

I am stuck in this program for the last 5 days please help me out.The output which I had got is entirely different from the desired output.Please its urgent
The program is to read a positive integer number n, and generate the numbers in the following way. (eg: if the entered number is 4 output will be as follows.
4! 3! 2! 1! 0 1! 2! 3! 4! 5!

positive integer

onruli — Fri, 27 Nov 2009 15:21:26 GMT

I am a new person to c programming but i know some of its fundamentals if someone could help me out in this program it would be of great help.
The program is to read a positive integer number n, and perform the squares of individual digits. For example n=205 then output will be 25 0 4

Ordering without sorting algorithm

fedya — Fri, 27 Nov 2009 14:08:36 GMT

Hello guys, I've got a question related to my data structures class.

I have file in which data is unordered. Say:

hello
apple
blue
phone
number

I have to search a string using Binary Search. But since we cannot apply Binary Search to unordered list, we should make an ordered list using some sorting algorithms.

However, main point of my assignment is making an ordered list without using any sorting algorithms and then apply Binary Search.

Question is how can I make data in my file an ordered?

Any help will be highly appreciated!

how is this programm working?

Iam3R — Fri, 27 Nov 2009 10:37:54 GMT

Hi ,

I read that c is not a block structured language.
means it does not allow defining functions inside other functions.

but this code is not generating any error not even warnings, though we nest the functions.

whats the story.

#include

int main()      {

        int num;

        num = 10;

        int fun(int n)  {

                printf("The local function");

                return 0;

        }

        fun(num);

        printf("Main function");

        return 0;

        }

[HELP]Averaging Filter 24bit BMP

imagine88 — Fri, 27 Nov 2009 07:34:39 GMT

Logic Used:
Insert Pixel Data into a struct containing RGB values of the pixels
read Data in a 3x3 array: | BGR(-1,-1) | BGR(-1,0) | BGR(-1,1) |
| BGR(0,-1) | BGR(0,0) | BGR(0,1) |
| BGR(1,-1) | BGR(1,0) | BGR(1,1) |
Assign Average of all Blue,Green,Red components respectively to another struct containing RGB values and write the same
to the output file

Problem:Unexpected output,as seen in the bmp files attached in mail.The output image is supposed to be almost the same,except a little blurred.

Input File: o.bmp
Output File: q.bmp

#define MASKSIZE 3

#define INFILE "o.bmp"

#define OUTFILE "q.bmp"



/*------------Algorithm(Using Mask 3x3)---------------------------*/



  fp1=fopen(INFILE,"rb");

  fp3=fopen(OUTFILE2,"wb"); 



  fread((BYTE *)&bmfh,sizeof(BITMAPFILEHEADER),1,fp1);

  fread((BYTE *)&bmih,sizeof(BITMAPINFOHEADER),1,fp1);

  fwrite((BYTE *)&bmfh,sizeof(BITMAPFILEHEADER),1,fp3);

  fwrite((BYTE *)&bmih,sizeof(BITMAPINFOHEADER),1,fp3);

  fseek(fp1,bmfh.bfOffsetBits,SEEK_SET);     /*Set Position to Start of Pixel Data*/



  row=0;      /*Offset for Row of Bitmap Array*/

  /*Begin Loop*/

  while(row
    {

      col=0;         /*Offset for Column of Bitmap Array*/

      while(col
      {

        fseek(fp1,(bmfh.bfOffsetBits)+(row * (bmih.biWidth * 3))+(col),SEEK_SET);  /*Move to Next Pixel (central pixel on which mask coincides)*/



        pos=ftell(fp1);

        pos=pos-((bmih.biWidth *3) + MASKSIZE);

        if(row==0)

          {

            if(col==0)

            {

              fseek(fp1,0,SEEK_CUR);      /*for poition (0,0) read pixel from (0,0)*/

            }

            else

            {

              fseek(fp1,ftell(fp1)-3,SEEK_CUR);  /*for position(0,col) read pixel into array from previous pixel( - 3Bytes)*/

            }

          }

        else

          {

            if(col==0)

            {

              fseek(fp1,ftell(fp1)-(bmih.biWidth *3),SEEK_CUR);  /*for position(row,0) start reading into array from the pixel directly above current position*/

            }

            else

            {

              if(col == (bmih.biWidth)-1)

                {

                  fseek(fp1,ftell(fp1)-((bmih.biWidth+1)*3),SEEK_CUR); /*for poition(row,Width-1) read pixel data into array at position (-1,-1) in a 3x3 array*/

                }

              else

                {

                  fseek(fp1,ftell(fp1)-((bmih.biWidth+1)*3),SEEK_CUR); /*for position(row,col)*/

                }

            }

          }

        /*Begin Reading Pixel Data Into Array */

        for(rowoff=-1;rowoff<2;rowoff++)

          {

            for(coloff=-1;coloff<2;coloff++)

            {

              if(row==0) /*Padding*/

                {

                  rgb[-1][-1].rgbtBlue=rgb[-1][0].rgbtBlue=rgb[-1][2].rgbtBlue=0;

                  rgb[-1][-1].rgbtGreen=rgb[-1][0].rgbtGreen=rgb[-1][2].rgbtGreen=0;

                  rgb[-1][-1].rgbtRed=rgb[-1][0].rgbtRed=rgb[-1][2].rgbtRed=0;

                  rowoff++;

                }

              if(col==0) /*Padding*/

                {

                  rgb[-1][-1].rgbtBlue=rgb[0][-1].rgbtBlue=rgb[1][-1].rgbtBlue=0;

                  rgb[-1][-1].rgbtGreen=rgb[0][-1].rgbtGreen=rgb[1][-1].rgbtGreen=0;

                  rgb[-1][-1].rgbtRed=rgb[0][-1].rgbtRed=rgb[1][-1].rgbtRed=0;

                  coloff++;

                }

              fread(pixel,1,sizeof(RGBTRIPLE),fp1);

              rgb[rowoff][coloff].rgbtBlue=pixel->rgbtBlue;

              rgb[rowoff][coloff].rgbtGreen=pixel->rgbtGreen;

              rgb[rowoff][coloff].rgbtRed=pixel->rgbtRed;

              if(col==(bmih.biWidth-1)) /*Padding*/

                {

                  rgb[-1][1].rgbtBlue=rgb[0][1].rgbtBlue=rgb[1][1].rgbtBlue=0;

                  rgb[-1][1].rgbtGreen=rgb[0][1].rgbtGreen=rgb[1][1].rgbtGreen=0;

                  rgb[-1][1].rgbtRed=rgb[0][1].rgbtRed=rgb[1][1].rgbtRed=0;

                  coloff++;

                }

              if(row==(bmih.biHeight)) /*Padding*/

                {

                  rgb[1][-1].rgbtBlue=rgb[1][0].rgbtBlue=rgb[1][1].rgbtBlue=0;

                  rgb[1][-1].rgbtGreen=rgb[1][0].rgbtGreen=rgb[1][1].rgbtGreen=0;

                  rgb[1][-1].rgbtRed=rgb[1][0].rgbtRed=rgb[1][1].rgbtRed=0;

                  rowoff++;

                }

            }

            fseek(fp1,((bmih.biWidth)*3)+(MASKSIZE),SEEK_CUR);

          }

        /*Finish Read*/

        /*Begin Averaging Array color value*/

        for(i=-1;i<2;i++)

          {

            for(j=-1;j<2;j++)

            {

              Blue=(Blue+(rgb[i][j].rgbtBlue))/9;

              Green=(Green+(rgb[i][j].rgbtGreen))/9;

              Red=(Red+(rgb[i][j].rgbtRed))/9;

            }

          }

        /*Averaging Finish*/

        /*Write Averaged Values Into Fil*/

        pixel->rgbtBlue=Blue;

        pixel->rgbtGreen=Green;

        pixel->rgbtRed=Red;

        fwrite(pixel,1,sizeof(RGBTRIPLE),fp3);

        /*Finish Writing*/

        col++;

      }

      row++;

    }

  /*End Loop*/

Input Image:

Output Image:

Attached Images

	o.bmp (126.6 KB)
	q.bmp (126.6 KB)

System date in C

Mattpd — Fri, 27 Nov 2009 05:59:00 GMT

Sorry, solved my own problem.

Help with Code Tags

...

Question about newline character

rel0aded911 — Fri, 27 Nov 2009 00:02:30 GMT

can we type while ( "variable" = '\n') ? or an error will occur?

Small problem with structures

Mattpd — Thu, 26 Nov 2009 20:11:31 GMT

I am trying to take a user's input and assign it to a certain part of a structure. This code is in my book so I assume it's correct:

scanf("%d", &part_number);

inventory[num_parts].number = part_number;

I need to do the same thing but with a string instead of a number, but I get incompatible types in assignment error.

scanf("%s", &part_name);

inventory[num_parts].name = part_name;

How could I accomplish this?

Graphic programming

DavidBrown1 — Thu, 26 Nov 2009 15:05:29 GMT

I need help in Graphic programming in C. I donno how to start.
I use Visual C++ compiler which doesn't support
Please somebody help. I can't find anything!:sad:

Using pointers to find the sum of two matrices

imolorhe — Thu, 26 Nov 2009 12:54:02 GMT

Please, I need help in finding the sum of two matrices using pointers. Thanks.

it won't work the way i want it

D_switch — Thu, 26 Nov 2009 10:56:25 GMT

im using borland

/*Write a function that will scan/read each line of a given text file

and determine whether a line is valid or invalid. A line is said to be valid

if and only if it satisfies the ff:

a. the line is composed only of characters a and b

b. the line contains an equal number of a's and b's

The function must display valid/invalid as the case may be*/



# include 

# include 

# include 

# include 



void main(void)

{

        FILE *fp;

        char str[100];

        int i,stop,a,b;



        if((fp=fopen("detvalid.txt","rt"))!=NULL)

        {

         while (!feof(fp))

         {

                fgets(str,100,fp);

                stop=0;a=b=0;

                for(i=0;i
                {

                        if(str[i]=='a')

                        {

                                a++;

                        }

                        else if(str[i]=='b')

                        {

                                b++;

                        }

                        else

                        {

                                stop++;

                        }

                }

                 if (stop||a!=b)

                {

                        printf("invalid\n");

                }

                else

                {

                        printf("valid\n");

                }

         }

         fclose(fp);

        }

}

float and double precission

Iam3R — Thu, 26 Nov 2009 10:47:16 GMT

Hi
i have written a program to check the precision of float and double values.
i read that the precision of float is 6 digits and double is 10.
but it is showing only 6 for both.

do we need to make any arrangement for the system to print the correct precission.

[Shark@localhost Fresh]$ gcc flt_dbl_prec.c

[Shark@localhost Fresh]$ ./a.out

34.345676 

34.345678

[Shark@localhost Fresh]$ cat flt_dbl_prec.c

int  main()

{

        float f = 34.34567832;

        double d= 34.3456783221;

        printf("%f\n",f);

        printf("%lf\n",d);

return 0;

}

Light weight (opensource/free) IDE for C programming?

michelle1 — Thu, 26 Nov 2009 06:30:11 GMT

Hello,

Can anyone recommend an light weight IDE for C development? Preferably open source, but definitely free. (for Windows)

It doesn't need to have its own version control - I'm using subversion - a plugin to subversion would be nice but it okay if it doesn't.

Currently my colleague is using Borland C++ to develop and compile C code. It looks a little heavy and I'd prefer to use something much simpler.

Thanks in advance, Michelle

Threaded Socket Issue

patrickkonsor — Thu, 26 Nov 2009 01:31:39 GMT

Hello all,

I'm working on a school project (in C) that I'm having some issues with. I have a number of threads which recursively send information between one another via sockets. The structure for the recursive case is as follows..

Loop For A Long Time {
Receive From Predecessor
Respond To Predecessor
Process Info
Create Successor If Necessary
Send To Successor
Wait For Response From Successor
}

The first thread just processes info, sends it to the info, and waits for a response. The last thread just receives and processes info.

I'm having a problem that results from the following sequence of events (call a given thread B, its predecessor A, and its successor C): B sends some info to C and waits for a response, then A gets the CPU, computes some info, sends it to B, and waits for a response. At this point both A and B are blocking, so C goes and responds to B. Then B tries to get the info that A sent it. The problem is that sometimes the messages that A sent to B is no longer there (B receives something, because it stops blocking, but its zero length). B has separate sockets for A and C, so I don't believe any problem should arise from the fact that C sends a message to B (that is, B receives it as well) while A has a message that's waiting to be received by B. It would seem this is caused by a race condition, but there's no shared data that are written to.

Does anyone have any ideas as to why this might be happening?

The entirety of the code follows (it's quite long, sorry). The main is essentially a server that creates the new threads. sieve_thread is the recursive case, and every one runs in its own thread. initial is the base case, and runs in its own thread.

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 



#define PORT 57102

#define MSG_LENGTH 1000

#define LIST_LENGTH 500

#define RESULTS_LENGTH 1000000



int max;

int max_sqrt;



int done = -1;

int cont = 1;

int new = 0;



sem_t sem1;

sem_t sem2;

int most_recent_port = PORT;



void sieve_thread(void*);

void initial();



int main(int argc, char* argv[]) {



        char msg[MSG_LENGTH];

        int socket_main, socket_current, cc, fromlen, tolen;

        int addrlen;

        struct sockaddr_in me;

        struct sockaddr_in them;

        int result, response;

        int stop = 0;

        int yes = 1;



        sem_init(&sem1, 0, 0);

        sem_init(&sem2, 0, 0);



        sigset(SIGPIPE, SIG_IGN);



        // Get Socket

        socket_main = socket(AF_INET, SOCK_STREAM, 0);

        if (socket_main == -1) {

                perror("socket");

                exit(1);

        }

        if (setsockopt(socket_main, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {

                perror("setsockopt");

                close(socket_main);

                exit(1);

        }



        // Build My Struct

        memset(&me, 0, sizeof(me));

        me.sin_family = AF_INET;

        me.sin_addr.s_addr = INADDR_ANY;

        me.sin_port = htons(PORT);



        // Bind

        printf("server bound to %i\n", PORT);

        result = bind(socket_main, (struct sockaddr *) &me, sizeof(struct sockaddr));

        if (result == -1) {

                perror("bind");

                close(socket_main);

                exit(1);

        }



        // Listen

        result = listen(socket_main, 20);

        if (result == -1) {

                perror("listen");

                close(socket_main);

                exit(1);

        }



        if (argc > 1) {

                max = atoi(argv[1]);

                pthread_t thread;

                pthread_create(&thread, NULL, (void*) &initial, NULL);

        }



        sem_wait(&sem1);



        while (!stop) {



                // Accept

                result = sizeof(struct sockaddr_in);

                socket_current = accept(socket_main, (struct sockaddr*) &them, &result);

                if (socket_current == -1) {

                        perror("accept");

                        close(socket_main);

                        exit(1);

                }



                // Recieve

                result = sizeof(struct sockaddr_in);

                memset(msg, '\0', MSG_LENGTH);

                result = recvfrom(socket_current, &response, sizeof(int), 0, (struct sockaddr*) &them, &result);

                if (result == -1) {

                        perror("recv (server 1)");

                        close(socket_current);

                        close(socket_main);

                        exit(1);

                }

                printf("server recieved: %i\n", response);



                if (response > 0) {

                        max = response;

                        max_sqrt = (int) sqrt(max) + 1;

                }



                // New Thread

                if (response >= 0) {



                        pthread_t thread;

                        pthread_create(&thread, NULL, (void*) &sieve_thread, (void*) (most_recent_port + 1));

                        sem_wait(&sem2);



                        printf("server sent: %i\n", most_recent_port);

                        result = sendto(socket_current, &most_recent_port, sizeof(int), 0, (struct sockaddr*) &them, sizeof(struct sockaddr_in));

                        if (result == -1) {

                                perror("send (server 1)");

                                close(socket_current);

                                close(socket_main);

                                exit(1);

                        }



                }



                if (response == -1) {

                        stop = 1;

                }



                close(socket_current);

        }



        // Close Stuff

        //close(socket_current);

        close(socket_main);

        sleep(1);

        printf("server exiting\n");

}



// Sieve Thread

void sieve_thread(void* _port) {



        char msg[MSG_LENGTH];

        int socket_server, socket_server_sub, socket_predecessor, socket_predecessor_sub, socket_successor, socket_successor_sub;

        struct sockaddr_in me;

        struct sockaddr_in server;

        struct sockaddr_in successor;

        struct sockaddr_in predecessor;

        int result, response, response_length;

        int stop = 0, stop_all = 0;

        int list_recieve[LIST_LENGTH];

        int list_recieve_length;

        int list_send[LIST_LENGTH];

        int list_results[RESULTS_LENGTH];

        int* list_tmp;

        int list_tmp_index = 0;

        int i, j, k = 0, x = 0, yes = 1;

        int prime = 0;

        struct hostent* host;

        int created_successor = 0;

        int port = (int) _port;



        // Get Predecessor Socket

        socket_predecessor = socket(AF_INET, SOCK_STREAM, 0);

        if (socket_predecessor == -1) {

                printf("Error: socket 1 (thread %i)\n", (int) port);

                perror("socket");

                exit(1);

        }

        if (setsockopt(socket_predecessor, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {

                perror("setsockopt");

                close(socket_predecessor);

                exit(1);

        }



        // Build My Struct

        memset(&me, 0, sizeof(me));

        me.sin_family = AF_INET;

        me.sin_addr.s_addr = INADDR_ANY;

        me.sin_port = htons(port);



        // Bind

        while ((result = bind(socket_predecessor, (struct sockaddr *) &me, sizeof(struct sockaddr))) == -1) {

                me.sin_port = htons(port++);

                printf("thread %i bind collision\n", port);

                //result = bind(socket_predecessor, (struct sockaddr *) &me, sizeof(struct sockaddr));

                /*if (result == -1) {

                 printf("Error: bind (thread %i)\n", (int)port);

                 perror("bind (thread 1)");

                 close(socket_predecessor);

                 exit(1);

                 }*/

        }

        most_recent_port = port;

        printf("thread bound to %i (%i)\n", port, (int)_port);



        // Listen For Predecessor

        result = listen(socket_predecessor, 20);

        if (result == -1) {

                perror("listen");

                close(socket_predecessor);

                exit(1);

        }

        printf("thread %i listening\n", (int) port);



        sem_post(&sem2);



        // Accept From Predecessor

        result = sizeof(struct sockaddr_in);

        socket_predecessor_sub = accept(socket_predecessor, (struct sockaddr*) &predecessor, &result);

        if (socket_predecessor_sub == -1) {

                printf("Error: accept (thread %i)\n", (int) port);

                perror("accept (1 in thread)");

                close(socket_predecessor);

                exit(1);

        }



        memset(list_send, 0, LIST_LENGTH);



        while (!stop) {

                printf("thread %i accepting\n", (int) port);



                // Recieve list from predecessor

                memset(list_recieve, 0, LIST_LENGTH);

                result = sizeof(struct sockaddr_in);

                response_length = recvfrom(socket_predecessor_sub, list_recieve, LIST_LENGTH * sizeof(list_recieve), 0, (struct sockaddr*) &predecessor, &result);

                if (response_length == -1) {

                        printf("Error: recv 1 (thread %i)\n", (int) port);

                        perror("recv (thread 1)");

                        close(socket_predecessor_sub);

                        close(socket_predecessor);

                        close(socket_successor_sub);

                        close(socket_successor);

                        exit(1);

                }

                printf("thread %i recieved (1): %i, length: %i\n", (int) port, list_recieve[0], response_length);



                // If our predecessor isn't done sending

                if (list_recieve[0] != -1 && response_length != 0) {

                        list_recieve_length = response_length / sizeof(int);



                        // Send response to predecessor so they can continue

                        printf("thread %i sent (1): %i\n", (int) port, cont);

                        result = sendto(socket_predecessor_sub, &cont, sizeof(cont), 0, (struct sockaddr*) &predecessor, sizeof(struct sockaddr_in));

                        if (result == -1) {

                                printf("Error: send 1 (thread %i)\n", (int) port);

                                perror("send (thread 1)");

                                close(socket_predecessor_sub);

                                close(socket_predecessor);

                                close(socket_successor_sub);

                                close(socket_successor);

                                exit(1);

                        }



                        // Set Prime

                        if (prime == 0) {

                                prime = list_recieve[0];

                                if (prime >= max_sqrt) {

                                        stop_all = 1;

                                        printf("STOP ALL (thread %i) -------------------------\n", (int) port);

                                        list_tmp = (int*) malloc(RESULTS_LENGTH * sizeof(int));

                                        memset(list_tmp, 0, RESULTS_LENGTH * sizeof(int));

                                }

                        }



                        if (!stop_all) {

                                // Update send list

                                printf("thread %i recieved entries: %i, prime: %i\n", (int) port, (response_length / sizeof(int)), prime);

                                for (i = 0; i < list_recieve_length && k < LIST_LENGTH; i++) {

                                        //printf("   thread %i testing %i\n", (int)port, list_recieve[i]);

                                        if (list_recieve[i] % prime != 0 && list_recieve > 0) {

                                                list_send[k++] = list_recieve[i];

                                        }

                                }

                        } else {

                                for (i = 0; i < list_recieve_length && k < LIST_LENGTH; i++) {

                                        //printf("   thread %i storing %i\n", (int)port, list_recieve[i]);

                                        list_tmp[list_tmp_index++] = list_recieve[i];

                                }

                        }



                } else {

                        stop = 1;

                }



                // Send list to successor

                if ((k > 1 || (stop && k > 1)) && !stop_all) {

                //if ((k == LIST_LENGTH || (stop && k > 1)) && !stop_all) {



                        // Create Successor

                        if (!created_successor) {

                                printf("thread %i creating successor\n", (int) port);



                                // Create Server Socket

                                socket_server = socket(AF_INET, SOCK_STREAM, 0);

                                if (socket_server == -1) {

                                        perror("socket");

                                        close(socket_predecessor_sub);

                                        close(socket_predecessor);

                                        exit(1);

                                }



                                // Build Server Struct

                                memset(&server, 0, sizeof(server));

                                server.sin_family = AF_INET;

                                server.sin_port = htons(PORT);

                                host = gethostbyname("mikey.cs.uwec.edu");

                                inet_aton(host->h_addr, &(server.sin_addr));



                                // Connect to Server

                                printf("thread %i connecting to %i\n", (int) port, PORT);

                                socket_server_sub = connect(socket_server, (struct sockaddr *) &server, sizeof(server));

                                if (socket_server_sub == -1) {

                                        perror("socket");

                                        close(socket_server);

                                        close(socket_predecessor_sub);

                                        close(socket_predecessor);

                                        close(socket_successor_sub);

                                        close(socket_successor);

                                        exit(1);

                                }



                                // Send Port Request to Server

                                printf("thread %i sent (2): %i\n", (int)port, new);

                                result = sendto(socket_server, &new, sizeof(new), 0, (struct sockaddr*) &server, sizeof(struct sockaddr_in));

                                if (result == -1) {

                                        printf("Error: send 2 (thread %i)\n", (int) port);

                                        perror("send (thread 2)");

                                        close(socket_server_sub);

                                        close(socket_server);

                                        close(socket_predecessor_sub);

                                        close(socket_predecessor);

                                        exit(1);

                                }



                                // Recieve Successor Port

                                result = sizeof(struct sockaddr_in);

                                result = recvfrom(socket_server, &response, sizeof(response), 0, (struct sockaddr*) &server, &result);

                                if (result == -1) {

                                        printf("Error: recv 2 (thread %i)\n", (int) port);

                                        perror("recv (thread 2)");

                                        close(socket_server_sub);

                                        close(socket_server);

                                        close(socket_predecessor_sub);

                                        close(socket_predecessor);

                                        exit(1);

                                }

                                printf("thread %i recieved (2): %i\n", (int) port, response);



                                // Disconnect From Server

                                close(socket_server_sub);

                                close(socket_server);



                                // Connect to successor if the server gave us one

                                if (response != -1) {



                                        // Create Sucessor Socket

                                        socket_successor = socket(AF_INET, SOCK_STREAM, 0);

                                        if (socket_successor == -1) {

                                                perror("socket");

                                                close(socket_predecessor_sub);

                                                close(socket_predecessor);

                                                exit(1);

                                        }



                                        // Build Successor Struct

                                        memset(&successor, 0, sizeof(successor));

                                        successor.sin_family = AF_INET;

                                        successor.sin_port = htons(response);

                                        host = gethostbyname("data.cs.uwec.edu");

                                        inet_aton(host->h_addr, &(successor.sin_addr));



                                        // Connect to Successor

                                        printf("thread %i connecting to %i\n", (int) port, response);

                                        socket_successor_sub = connect(socket_successor, (struct sockaddr *) &successor, sizeof(successor));

                                        if (socket_successor_sub == -1) {

                                                perror("socket");

                                                close(socket_predecessor_sub);

                                                close(socket_predecessor);

                                                close(socket_successor);

                                                exit(1);

                                        }

                                }



                                created_successor = 1;

                        }



                        if (created_successor) {



                                // Send list to successor

                                printf("thread %i sent (3): %i, length: %i\n", (int) port, list_send[0], k * sizeof(int));

                                result = sendto(socket_successor, list_send, k * sizeof(int), 0, (struct sockaddr*) &successor, sizeof(struct sockaddr_in));

                                if (result == -1) {

                                        printf("Error: send 3 (thread %i)\n", (int) port);

                                        perror("send (thread 3)");

                                        close(socket_predecessor_sub);

                                        close(socket_predecessor);

                                        close(socket_successor_sub);

                                        close(socket_successor);

                                        exit(1);

                                }



                                // Get Response

                                result = sizeof(struct sockaddr_in);

                                result = recvfrom(socket_successor, &response, sizeof(int), 0, (struct sockaddr*) &successor, &result);

                                if (result == -1) {

                                        printf("Error: recv 3 (thread %i)\n", (int) port);

                                        perror("recv (thread 3)");

                                        close(socket_predecessor_sub);

                                        close(socket_predecessor);

                                        close(socket_successor_sub);

                                        close(socket_successor);

                                        exit(1);

                                }

                                printf("thread %i recieved (3): %i\n", (int) port, response);



                                k = 0;

                                memset(list_send, 0, LIST_LENGTH);



                        }

                }



        }

        printf("thread %i done with loop\n", (int) port);



        // Prepare Results

        memset(list_results, 0, RESULTS_LENGTH * sizeof(int));



        // If not last

        if (created_successor) {



                // Send done signal to successor

                printf("thread %i sent (4): %i\n", port, done);

                result = sendto(socket_successor, &done, sizeof(int), 0, (struct sockaddr*) &successor, sizeof(struct sockaddr_in));

                if (result == -1) {

                        printf("Error: send 4 (thread %i)\n", (int) port);

                        perror("send (thread 4)");

                        close(socket_predecessor_sub);

                        close(socket_predecessor);

                        close(socket_successor_sub);

                        close(socket_successor);

                        exit(1);

                }



                // Wait for successors results

                printf("thread %i waiting\n", (int) port);

                result = sizeof(struct sockaddr_in);

                response_length = recvfrom(socket_successor, &list_results, RESULTS_LENGTH * sizeof(int), 0, (struct sockaddr*) &successor, &result);

                if (response_length == -1) {

                        printf("Error: recv 4 (thread %i)\n", (int) port);

                        perror("recv (thread 4)");

                        close(socket_predecessor_sub);

                        close(socket_predecessor);

                        close(socket_successor_sub);

                        close(socket_successor);

                        exit(1);

                }

                printf("thread %i recieved (4): %i, length: %i\n", (int) port,

                                list_results[0], response_length);

                k = response_length / sizeof(int) + 1;

                list_results[k - 1] = prime;

                printf("appending prime: %i\n", prime);

        }



        // If last, add all that remains in list

        else {

                printf("thread %i creating results list\n", (int) port);

                k = 0;

                for (i = list_tmp_index - 1; i > 0; i--) {

                        printf("PRIME: %i\n", list_results[i]);

                        list_results[k++] = list_tmp[i];

                }

                printf("PRIME: %i\n", prime);

                list_results[k++] = prime;

        }



        // Send results to predecessor

        printf("thread %i sent (5): %i, length: %i\n", (int) port, list_results[0], k * sizeof(int));

        result = sendto(socket_predecessor_sub, &list_results, k * sizeof(int), 0, (struct sockaddr*) &predecessor, sizeof(struct sockaddr_in));

        if (result == -1) {

                printf("Error: send 5 (thread %i)\n", (int) port);

                perror("send (thread 5)");

                close(socket_successor_sub);

                close(socket_successor);

                close(socket_predecessor_sub);

                close(socket_predecessor);

                exit(1);

        }



        close(socket_successor_sub);

        close(socket_successor);

        close(socket_predecessor_sub);

        close(socket_predecessor);



        printf("thread %i exiting\n", (int) port);

}



void initial() {

        int socket_main, socket_server, socket_thread;

        struct sockaddr_in server, thread;

        struct hostent* host;

        int result, response, i, j, k;

        int yes = 1;

        char msg[MSG_LENGTH];

        int list[LIST_LENGTH];

        int list_results[RESULTS_LENGTH];



        // Create Server Socket

        socket_main = socket(AF_INET, SOCK_STREAM, 0);

        if (socket_main == -1) {

                perror("socket");

                exit(1);

        }



        // Build Server Struct

        memset(&server, 0, sizeof(server));

        server.sin_family = AF_INET;

        server.sin_port = htons(PORT);

        host = gethostbyname("mikey.cs.uwec.edu");

        inet_aton(host->h_addr, &(server.sin_addr));



        // Connect to Server

        printf("base connecting to %i\n", PORT);

        socket_server = connect(socket_main, (struct sockaddr *) &server, sizeof(server));

        if (socket_server == -1) {

                perror("socket");

                close(socket_main);

                exit(1);

        }



        // Send Port Request to Server

        printf("base sent: %i\n", max);

        result = sendto(socket_main, &max, sizeof(max), 0, (struct sockaddr*) &server, sizeof(struct sockaddr_in));

        if (result == -1) {

                perror("send (base 1)");

                close(socket_server);

                close(socket_main);

                exit(1);

        }



        sem_post(&sem1);



        // Recieve Port

        result = sizeof(struct sockaddr_in);

        result = recvfrom(socket_main, &response, sizeof(response), 0, (struct sockaddr*) &server, &result);

        if (result == -1) {

                perror("recv (base 1)");

                close(socket_server);

                close(socket_main);

                exit(1);

        }

        printf("base recieved (1): %i\n", response);



        // Disconnect

        close(socket_server);

        close(socket_main);



        // Create Thread Socket

        socket_main = socket(AF_INET, SOCK_STREAM, 0);

        if (socket_main == -1) {

                perror("socket");

                exit(1);

        }



        // Build Thread Struct

        memset(&thread, 0, sizeof(thread));

        thread.sin_family = AF_INET;

        thread.sin_port = htons(response);

        host = gethostbyname("data.cs.uwec.edu");

        inet_aton(host->h_addr, &(thread.sin_addr));



        // Connect to Thread

        printf("base connecting to %i\n", response);

        socket_thread = connect(socket_main, (struct sockaddr *) &thread,

                        sizeof(thread));

        if (socket_thread == -1) {

                perror("socket");

                close(socket_main);

                exit(1);

        }



        // Build & Send List

        memset(list, 0, LIST_LENGTH);

        for (i = 2, j = 0; i <= max; i++) {

                list[j] = i;

                j++;



                // Send Message

                if (j == LIST_LENGTH) {

                        printf("base sent: %i, length: %i\n", list[0], j * sizeof(int));

                        result = sendto(socket_main, list, j * sizeof(int), 0, (struct sockaddr*) &thread, sizeof(struct sockaddr_in));

                        if (result == -1) {

                                perror("send (base 2)");

                                close(socket_thread);

                                close(socket_main);

                                exit(1);

                        }



                        // Get Response

                        result = sizeof(struct sockaddr_in);

                        result = recvfrom(socket_main, &response, sizeof(int), 0, (struct sockaddr*) &thread, &result);

                        if (result == -1) {

                                perror("recv (base 2)");

                                close(socket_thread);

                                close(socket_main);

                                exit(1);

                        }

                        printf("base recieved (2): %i\n", response);

                        memset(msg, '\0', MSG_LENGTH);



                        j = 0;

                }

        }



        // Send Message

        if (j > 0) {

                printf("base sent: %i, length: %i\n", list[0], j * sizeof(int));

                result = sendto(socket_main, list, j * sizeof(int), 0, (struct sockaddr*) &thread, sizeof(struct sockaddr_in));

                if (result == -1) {

                        perror("send (base 3)");

                        close(socket_thread);

                        close(socket_main);

                        exit(1);

                }



                // Get Response

                result = sizeof(struct sockaddr_in);

                result = recvfrom(socket_main, &response, sizeof(int), 0, (struct sockaddr*) &thread, &result);

                if (result == -1) {

                        perror("recv (base 3)");

                        close(socket_thread);

                        close(socket_main);

                        exit(1);

                }

                printf("base recieved (3): %i\n", response);



        }



        // Send Message

        printf("base sent: %i\n", done);

        result = sendto(socket_main, &done, sizeof(int), 0, (struct sockaddr*) &thread, sizeof(struct sockaddr_in));

        //result = send(socket_main, &done, sizeof(int), 0);

        if (result == -1) {

                perror("send (base 4)");

                close(socket_thread);

                close(socket_main);

                exit(1);

        } else {

                printf("base sent length: %i\n", result);

        }



        // Get Response

        printf("base waiting\n");

        result = sizeof(struct sockaddr_in);

        result = recvfrom(socket_main, &list_results, RESULTS_LENGTH * sizeof(int), 0, (struct sockaddr*) &thread, &result);

        if (result == -1) {

                perror("recv (base 4)");

                close(socket_thread);

                close(socket_main);

                exit(1);

        }



        for (i = result / sizeof(int) - 1; i >= 0; i--) {

                printf("%i\n", list_results[i]);

        }



        // Close the Sockets

        close(socket_thread);

        close(socket_main);



        // Create Thread Socket

        socket_main = socket(AF_INET, SOCK_STREAM, 0);

        if (socket_main == -1) {

                perror("socket");

                exit(1);

        }



        // Connect to Thread

        printf("base connecting to %i\n", response);

        socket_thread = connect(socket_main, (struct sockaddr *) &server, sizeof(server));

        if (socket_thread == -1) {

                perror("socket");

                close(socket_main);

                exit(1);

        }



        result = sendto(socket_main, &done, sizeof(int), 0, (struct sockaddr*) &server, sizeof(struct sockaddr_in));

        if (result == -1) {

                perror("send (base 5)");

                close(socket_server);

                close(socket_main);

                exit(1);

        }



        // Give client a chance to properly shutdown

        //      sleep(10);

        printf("base exiting\n");



}

Here is some sample output. The thread 57103 receives a 0 length message at line 63, but it should've received the 2000 byte message sent by base at line 40.

[konsorpc@mikey project3]$ sieve 2000

server bound to 57102

base connecting to 57102

base sent: 2000

server recieved: 2000

thread bound to 57103 (57103)

thread 57103 listening

server sent: 57103

base recieved (1): 57103

base connecting to 57103

base sent: 2, length: 2000

thread 57103 accepting

thread 57103 recieved (1): 2, length: 2000

thread 57103 sent (1): 1

thread 57103 recieved entries: 500, prime: 2

thread 57103 creating successor

base recieved (2): 1

base sent: 502, length: 2000

thread 57103 connecting to 57102

thread 57103 sent (2): 0

server recieved: 0

thread bound to 57104 (57104)

thread 57104 listening

server sent: 57104

thread 57103 recieved (2): 57104

thread 57103 connecting to 57104

thread 57103 sent (3): 3, length: 1000

thread 57104 accepting

thread 57104 recieved (1): 3, length: 1000

thread 57104 sent (1): 1

thread 57104 recieved entries: 250, prime: 3

thread 57104 creating successor

thread 57103 recieved (3): 1

thread 57103 accepting

thread 57103 recieved (1): 502, length: 2000

thread 57103 sent (1): 1

thread 57103 recieved entries: 500, prime: 2

thread 57103 sent (3): 503, length: 1000

base recieved (2): 1

base sent: 1002, length: 2000

thread 57104 connecting to 57102

thread 57104 sent (2): 0

server recieved: 0

thread bound to 57105 (57105)

thread 57105 listening

server sent: 57105

thread 57104 recieved (2): 57105

thread 57104 connecting to 57105

thread 57104 sent (3): 5, length: 664

thread 57105 accepting

thread 57105 recieved (1): 5, length: 664

thread 57105 sent (1): 1

thread 57105 recieved entries: 166, prime: 5

thread 57105 creating successor

thread 57104 recieved (3): 1

thread 57104 accepting

thread 57104 recieved (1): 503, length: 1000

thread 57104 sent (1): 1

thread 57104 recieved entries: 250, prime: 3

thread 57104 sent (3): 503, length: 668

thread 57103 recieved (3): 1

thread 57103 accepting

thread 57103 recieved (1): 0, length: 0

thread 57103 done with loop

thread 57105 connecting to 57102

thread 57105 sent (2): 0

server recieved: 0

thread bound to 57106 (57106)

thread 57106 listening

server sent: 57106

thread 57105 recieved (2): 57106

thread 57105 connecting to 57106

thread 57105 sent (3): 7, length: 532

thread 57106 accepting

thread 57106 recieved (1): 7, length: 532

thread 57106 sent (1): 1

thread 57106 recieved entries: 133, prime: 7

thread 57106 creating successor

thread 57105 recieved (3): 1

thread 57105 accepting

thread 57105 recieved (1): 503, length: 668

thread 57105 sent (1): 1

thread 57105 recieved entries: 167, prime: 5

thread 57105 sent (3): 503, length: 532

thread 57104 recieved (3): 1

thread 57104 accepting

thread 57104 recieved (1): 1002, length: 2000

thread 57104 sent (1): 1

thread 57104 recieved entries: 500, prime: 3

thread 57104 sent (3): 1003, length: 1332

base recieved (2): 1

base sent: 1502, length: 1996

thread 57106 connecting to 57102

thread 57106 sent (2): 0

server recieved: 0

thread bound to 57107 (57107)

thread 57107 listening

server sent: 57107

thread 57106 recieved (2): 57107

thread 57106 connecting to 57107

thread 57106 sent (3): 11, length: 456

thread 57107 accepting

thread 57107 recieved (1): 11, length: 456

thread 57107 sent (1): 1

thread 57107 recieved entries: 114, prime: 11

thread 57107 creating successor

thread 57106 recieved (3): 1

thread 57106 accepting

thread 57106 recieved (1): 503, length: 532

thread 57106 sent (1): 1

thread 57106 recieved entries: 133, prime: 7

thread 57106 sent (3): 503, length: 452

thread 57105 recieved (3): 1

thread 57105 accepting

thread 57105 recieved (1): 0, length: 0

thread 57105 done with loop

thread 57107 connecting to 57102

thread 57107 sent (2): 0

server recieved: 0

thread bound to 57108 (57108)

thread 57108 listening

server sent: 57108

thread 57107 recieved (2): 57108

thread 57107 connecting to 57108

thread 57107 sent (3): 13, length: 412

thread 57108 accepting

thread 57108 recieved (1): 13, length: 412

thread 57108 sent (1): 1

thread 57108 recieved entries: 103, prime: 13

thread 57108 creating successor

thread 57107 recieved (3): 1

thread 57107 accepting

thread 57107 recieved (1): 503, length: 452

thread 57107 sent (1): 1

thread 57107 recieved entries: 113, prime: 11

thread 57107 sent (3): 503, length: 412

thread 57106 recieved (3): 1

thread 57106 accepting

thread 1956 recieved (1): 1003, length: 3328

thread 1956 sent (1): 1

Error: send 1 (thread 1956)

send (thread 1): Bad file descriptor

Mysql C API and Asterisk AGI

ContactaCall — Thu, 26 Nov 2009 01:22:58 GMT

Hello. I'm currently developing an IVR system under Asterisk through the Asterisk Gateway Interface (AGI), connecting to a Mysql server using the Mysql C API.
The server returns a ticket number that I have to say to the client, so I developed a TTS (Text To Speech) algorithm to say a specific number (13000) to the client for testing, by using the AGI application Stream File, and playing two sound files back to back, thirteen.gsm and thousand.gsm, so the caller can hear the ticket number "Thirteen Thousand"
The problem is this: on the Asterisk debug console I can see that the Stream File ("thirteen") and Stream File("thousand") functions work, but can hear no sound whatsoever on the softphone. The sound files play fine on other sound players and so do other AGI applications using the Stream File function.

The code below basically copies the number returned by the server (13000 for this test) on the array 'numero', then checks the first and second numbers to be '1' and '3' (I omit the latter since I know they're zero) then play the files through the AGI functions Stream File.
I'm guessing it has to do with being connected to the server while playing files or something.
Any ideas?

while ((row = mysql_fetch_row(res)) != NULL)

        {

                strcpy(prueba[0],row[0]);

                j=strlen(prueba[0]);

                for (i=0; i
                {

                        if (prueba[0][i]=='0' || prueba[0][i]=='1' || prueba[0][i]=='2' || prueba[0][i]=='3' || prueba[0][i]=='4' || prueba[0][i]=='5' ||

                                prueba[0][i]=='6' || prueba[0][i]=='7' || prueba[0][i]=='8' || prueba[0][i]=='9')

                                                        

                        {

                                //printf("El string comienza en posicion %i\n",i);

                                l=i;

                                for (k=i; k
                                {

                                        m=k;                                        

                                        if (prueba[0][k]=='\0')

                                        {

                                                //printf("El string termina en posicion %i\n",k);

                                                k=j;        

                                        }

                                }

                                i=j;

                        }        

                }

                n=m-l;

                int numero[n];        

                //printf("Variable 'numero' tiene %i espacios\n",n+1);

                i=0;

                for (j=l;j<(m+1);j++)

                {                        

                        numero[i]=prueba[0][j];

                        i++;

                }

                /*for (i=0;i<(n+1);i++)

                {        

                        printf("%c",numero[i]);

                }*/

                

/*-------------------------------------------------*/

        /*TTS para numero*/

                switch(n+1)

                {        



                        /* Ticket de 5 digitos */

                        case 5:

                                if (numero[0]=='1')

                                        //printf("prueba\n");                                        

                                        UnidadMil(numero[1]);

                

                }

                

        }

void UnidadMil(int unidad)

{

        switch (unidad){

                case '3':

                        StreamFile("trece");

                        StreamFile("mil");

        }



}

void StreamFile(char *audio)

{

        char line [80];

        setlinebuf(stdout);

        setlinebuf(stderr);

        printf("STREAM FILE %s #""\n", audio); 

        fgets(line,80,stdin);                                  

        fputs(line,stderr);                           

        fflush(stdin);

}

optimize my code

9868 — Wed, 25 Nov 2009 13:46:55 GMT

Hello everyone,
Here's my code for making a dynamic array(the user inputs the size of the array). It's working fine but I think that I've not made the best code. Is there any suggestion for improvement or optimization?

#include 

#include 

int main(void)

{

        int *p;

        int n,i;

        printf("how many integers do u wanna enter\n");

        scanf("%d",&n);

        p=malloc(n*sizeof(int));

        for(i=0;i
        {

                printf("enter the %d element",i+1);

                scanf("%d",p);

                p++;

        }

        p=p-n;

        for(i=0;i
        {

                printf("%d\n",*(p+i));

        }

        free(p);

}

info

pdk123 — Wed, 25 Nov 2009 13:24:41 GMT

In the following c code, the num_elements is gobal.
But if i make it as local and return , it gives strange value just before return it becomes '0' ...can anybody explain why ?

int num_elements =0;

//generates a psuedo-random integer between min and max

int randint(int min, int max)

{

    if (min>max)

    {

        return max+int((min-max+1)*rand()/(RAND_MAX+1.0));

    }

    else

    {

        return min+int((max-min+1)*rand()/(RAND_MAX+1.0));

    }

} 



unsigned int sample(unsigned int m, unsigned int n, unsigned int *set)

{

        unsigned int t, i;

        unsigned int j,l;



        if (m==0)

                return 0;

        else

        {

                l=sample(m-1, n-1, set);

      

                t = randint(1,n);

         

                if(num_elements !=0)

                {

                   for (i=0; i 
                   {

                      if ( t == set[i])

                      {

                               /* add t to s */

                             set[num_elements] = t;

                      }

                      else

                      {

                             /* add to n to s; */

                             set[num_elements] = n;

                             break;

                      } 

                   }

                }

                else

                {

                        set[num_elements] = t;

                }



        }

            j= num_elements++;

        printf("%d", num_elements);

                return j;

}



int _tmain(int argc, _TCHAR* argv[])

{

        unsigned int a = 2, b=4;

        unsigned int set[10];

        num_elements=0;

    sample(a, b, set);



        printf("%d", num_elements);



        Sleep(10000);



        return 0;

}

Need help starting dice problem

applesplz — Wed, 25 Nov 2009 03:56:27 GMT

Hey everyone, I am stuck on the last function of my problem, could someone help me get started by helping me on the first part of function?

Question:
I need to write a random function to get 2 numbers from 1-6, and needs to be in a loop 25 times or until both numbers are 6

Thanks For Any Help.

need help with searching function for string

student1t — Tue, 24 Nov 2009 20:52:17 GMT

Hi, I am trying to search for a word I have entered into a list. I could list all entries so far. But I am having a hard time figuring out a function that can search for a particular word on the list. Below are the codes. I commented out different functions I have tried. Thank you!

boolean searchWord (VOCAB V[])



  {

         int i;

         char target[LENGTH];

        

         

             printf("\nEnter the Word you want to search: "); 

             fflush (stdin);

             gets (target);  

             

            for ( i=0; i
             {

            // if ( target == V[i].Word )

             //if ( strcmp( target, V[i].Word ) == 0);

             

              

              if (strncmp (V[i].Word,"target") == 0)



                 {

                  return 0;

                  }             

                 return 1;    

           }

     }

Assignment in C help ( factorial)

John-5- — Tue, 24 Nov 2009 20:27:19 GMT

Hi i'm having some trouble getting my head around this assignment...
which is :
Design, write and test a program to print a table of factorials. The program should read in two values: a maximum factorial value and a minimum factorial value.
It must then print a table, as illustrated below, with one column for the factorial number, one column for the factorial expression and a third column showing the result. The program must produce this table from maximum factorial value to the minimum factorial value; e.g. if the maximum factorial value is 5 and the minimum factorial value is 3 the program produces a table like the following:

Factorial value        Factorial Expression         Result

-----------------------------------------------------------------------------------

5!                                                 5*4*3*2*1                120

4!                                                  4*3*2*1                24

3!                                                      3*2*1                         6



------------------------------------------------------------------------------------

The program must repeatedly ask the user to input data and print a table of factorials, as illustrated above, until the user decides to exit the program.

so far i have been succesfull in creating the table reading in a maximum and min factorial and creating a list downwards to the left

what im finding hard is placing the 5*4*3 etc into the middle column

here is my code so far

#include 

#include



void main()

{

        // defining and initialising variables

    int max , factorial;

        int min=0;

    

    //enters a maximum factorial

        printf("Please enter a Maximum Factorial:");

        scanf("%d", &max);

    fflush(stdin);

    //enters a minimum factorial

        printf("\nPlease enter a Minimum factorial:");

        scanf("%d", &min);        

    fflush(stdin);

    //handles an input error

    if (max>min)

        printf("----------------------------------------------------------------------");

      else 

         printf("\nyou have entered an invalid number\n");

  

        printf("\nFactorial Value        Factorial expression        Factorial Result");

    printf("\n----------------------------------------------------------------------");

    //creating a list from max to min factorials

        factorial=max;

        while ( factorial>=min){

        printf("\n%d!" ,max);

        max=max-1;

        factorial=factorial-1;

        }



getch();

}

if anyone could help it would be hugely appreciated

How to get Motherboard information from C/C++ under Windows ?

AntonAL — Tue, 24 Nov 2009 16:09:42 GMT

Hi!

I develop the app, that must be binded to hardware-specific information.
This is a part of license protection scenario.
The serial number of motherboard must be obtained.

How to do it under Windows ?

Help with two programmes

SSc — Tue, 24 Nov 2009 14:14:20 GMT

Hi!
I'm new to programming and have difficulties in working out the following two examples:

hope someone can help me

usage of new keywords in c99

Iam3R — Tue, 24 Nov 2009 13:36:06 GMT

hi ,
i have read that c99 introduced:
inline,_Bool,restrict,_Complex,_Imaginary

i have used _Bool here but do no how to use remaining all
please any one used the above can help me.

int main()

{

    _Bool b;

      b=true;// giving error  true undeclared ,cant i use that way 

                 // with out using enums.

       b =1;

       if ( b )

           printf (" ok\n");

        else

           printf("No\n");

return 0;

}

Thanks,
Danian.

Need help getting started.

Mattpd — Tue, 24 Nov 2009 04:05:43 GMT

So I have this project to program an "auto parts management" C program. Basically I need to be able to add and delete lines of text from a text file. Also, I need to be able to edit lines of text. Lines of text are in the format:

PART NAME : OWNER : STATUS : SYSTEM DATE : CO NAME

Although I don't know much about them, structures would seem like they would be useful. I think in my case it would look like this:

struct parts

{

  char pname [PNAME_LEN+1];

  char owner [OWNER_LEN+1];

  char status [3];                                //toggles between in/out

  char date [10];                                // MM/DD/YYYY format.

  char oname [ONAME_LEN+1];

} part1, part2, part3;                         //etc... I assume I need a loop

                                                //to increment part.

To add a part, the program will prompt the user for a pname and an owner. So once I have those two things captured in variables, I need to initialize part1 so it contains "pname:owner:in" with the date and co name left blank. Will this work?

struct parts part1;

strcpy(part1.pname, pname);

strcpy(part1.oname, owner);

strcpy(part1.status, "in");

How would I then print part1 into a text file?

heap sort -- segmentation fault

klackey19 — Tue, 24 Nov 2009 01:59:42 GMT

I am writing a program that sorts an array of either floats or doubles -- this is specified at compile time via a command to the compiler. I also must use void pointers. My program compiles, but when I try to run it with floats I get a "segmentation fault" and when i try to run it with doubles I get a "illegal instruction" error message. Any suggestions?? Thanks in advance for your help!!

Here is the main, heapSort file, and header file: (the program also contains files for insert, merge, and bubble which you will see in the main and header but I am only concerned with the heap sort file)

//header file



#ifndef SRT_H

#define SRT_H



#include 



#define MAX_BUF 256



#define swap(qx,qy,sz)                                              \

do {                                                                \

    char buf[MAX_BUF];                                              \

    char *q1 = qx;                                                  \

    char *q2 = qy;                                                  \

    for (size_t m, ms = sz; ms > 0; ms -= m, q1 += m, q2 += m) {    \

        m = ms < sizeof(buf) ? ms : sizeof(buf);                    \

        memcpy(buf, q1, m);                                         \

        memcpy(q1, q2, m);                                          \

        memcpy(q2, buf, m);                                         \

    }                                                               \

} while (0)



void srtbubb(void *, size_t, size_t, int (*)(const void *, const void *));

void srtheap(void *, size_t, size_t, int (*)(const void *, const void *));

void srtinsr(void *, size_t, size_t, int (*)(const void *, const void *));

void srtmerg(void *, size_t, size_t, int (*)(const void *, const void *));



#endif /* SRT_H */



//main

#include 

#include 

#include 

#include "srt.h"



int compare(const void *, const void *);



int main(int argc, char *argv[]) {



    int size = argc == 2 ? atoi(argv[1]) : SHRT_MAX;



    TYPE *a = calloc(size, sizeof(TYPE));



#ifdef RAND

    for (int i = 0; i < size; ++i) {



        a[i] = (TYPE)rand() / RAND_MAX;

    }

#else

    for (int i = 0; i < size; ++i) {



        a[i] = i;

    }

#endif



#if defined BUBB

    srtbubb(a, size, sizeof(TYPE), compare);

#elif defined HEAP

    srtheap(a, size, sizeof(TYPE), compare);

#elif defined INSR

    srtinsr(a, size, sizeof(TYPE), compare);

#elif defined MERG

    srtmerg(a, size, sizeof(TYPE), compare);

#else

    qsort(a, size, sizeof(TYPE), compare);

#endif



#ifdef PRNT

    for (int i = 0; i < size; ++i) {



        printf("%f\n", a[i]);

    }

#else

    for (int i = 0; i < size - 1; ++i) {



        if (a[i] > a[i + 1]) {



            printf("fail\n");

            goto end;

        }

    }



    printf("pass\n");

#endif



end:



    free(a);



    return 0;

}



int compare(const void *p1, const void *p2) {



    if (*(TYPE *)p1 < *(TYPE *)p2) {



        return -5;

    }

    else if (*(TYPE *)p1 > *(TYPE *)p2) {



        return +5;

    }



    return 0;

}



//heap sort file

#include 

#include 

#include 

#include 

#include "srt.h"



void heapify (void *, size_t, size_t);

void siftdown(void *, char *, char *, size_t, size_t);

void srtheap(void *base, size_t nelem, size_t size, int (*compar)(const void *, const void *)) {

     

     heapify(base, nelem, size);    

     

     char *pEnd = (char *)base + ((nelem - 1) * size);

     

     while (pEnd > 0){

           swap(pEnd, base, size);

           pEnd -= size;

           siftdown(base, 0, pEnd, size, nelem);

           

     }

}



void heapify(void *pBase, size_t nelem, size_t size){

     

     char *pStart = (char *)pBase + (((nelem-2)/2) * size);     

     char *pEnd = (char *)pBase + ((nelem - 1) * size);

     

     while (pStart >= 0){

           pEnd -= size;

           siftdown(pBase, pStart, pEnd, size, nelem);

           pStart -= size;

     }

     return;

}



void siftdown(void *pBase, char * pStart, char * pEnd, size_t size, size_t nelem){



     char *pRoot;

     pRoot = pStart;

     size_t l = (nelem / 2);

     size_t r = (nelem - 1);

     

     while ((pRoot + (size * l)) <= pEnd){

           char *pChild;

           pChild = (pRoot + (size * l));

           if (((pChild + size) <= pEnd) && (pChild < (pChild + size)))

              pChild += size;

           if (pRoot < pChild){

              swap(pRoot, pChild, size);

              pRoot = pChild;

           }

           else

               return;

     }

     return;

}

Pointer arithmetic question

klackey19 — Tue, 24 Nov 2009 01:33:06 GMT

Hey everyone,

I'm coding a program in C and have a pointer called pRoot. I need to do (2 * pRoot) .. but the compiler says I cannot. Is there some legal way of implementing this pointer arithmetic?

Thanks in advance for your help!

buffer problem or undefined behaviour

Iam3R — Tue, 24 Nov 2009 01:20:42 GMT

enum fivenums {Z,O,T,TH,F,FI}

int main()

{

char ch;

int num;

do{

scanf("%d",&num);

switch(num)

{

case Z:

printf("ZERO\n");

break;

case O:

printf("ONE\n");

break;

case T:

printf("TWO\n");

break;

case TH:

printf("THREE\n");

break;

case F:

printf("FOUR\n");

break;

case FI:

printf("FIVE\n");

break;



default :

printf("Invalid\n");

break;

}

getchar();// to eat '\n' terminator so that it waits for below 

}

while ((ch =getchar())=='\n');

return 0;

}

in the above program if i input a number between 0 -3 its working fine.
but if the input is any alphabet i am getting a different out put;

for example:
my input is
1
o/p: ONE
2
o/p: TWO
and if its
a O/P is:
TWO
if i give a its giving the previously read input as out put
i.e 2.
and for any other alphabets also its giving the same o/p.
why is it giving the previous one.
when its already read from the buffer.

24 hour clock

amr123 — Mon, 23 Nov 2009 19:07:40 GMT

Hey guys,

i am writing a couple of programs but I have some problem with the basic one...

can you please provide me with a 24 hour clock which has hour, minute and second? also it should have the ability to set the time..

your help is highly appreciated...it is somehow urgent as i need to do the other programs based on this....

building my own primitive shell

DimaYasny — Mon, 23 Nov 2009 17:21:18 GMT

Hi all,

I'm helping my girl out with her hw, (/me not knowing C at all, but someone has to help, right?)
I am supposed to read user input, and then try to execute a given command plus the arguments in every given $PATH.

I managed it all, but I get puzzled by the execv function, which I am supposed to be using, it doesn't produce any stdio, and I can't seem to find a way to make it work

a basic command

execv ("/bin/touch", "/tmp/test123", NULL);

doesn't do anything, neither do I see an exit code.
How do I use it?

Here's what I've got so far:

void get_path_exec(char cmd[50])

{

    char command[50] = {0} ; //full command with path included

    char *tempcmd = NULL;

    char *result = NULL; //path iterator

    char *com[] = {0}; //command with args, no path

    char *arg = NULL; //list of arguments, path and command excluded

    char delims[] = ":"; //path iteration delimiter

    char delims1[] = " "; //

    char * path; //variable to hold the full path delimited by ':'

    int pid, status; //process flow control

    int argcount = 0; //argumetn counter, where 0 is the command

   

    tempcmd=cmd; //assign to temp variable, so strtok doesn't ruin cmd

    path=getenv("PATH");

    if (path != NULL)

        printf("Path is %s \n", path);

    else exit(1);    

        

    arg = strtok( tempcmd, delims1 ); 

    com[0] = arg; //place the command into com[0]

    while( arg )

    {

          argcount++;

          arg = strtok(NULL,delims1);

          com[argcount] = arg;

          printf("arg is %s \n", arg);

        }

        argcount++;

        com[argcount]=NULL; //last value in args should be NULL, right?



    result = strtok( path, delims ); 

    while( result ) 

    {

       strcpy(command, "");

       strcat(command, result);

       strcat(command, "/");

       strcat(command,cmd);

       strcat(command,"\0"); //gather all parts of full path'd command - path, "/" and cmdname

//       printf("full command: %s \n\n", command);

       

       if (( pid = fork()) == 0 ) //create a new process

        {

            execv(command, com);

//below is a point I don't get

            printf("Something happened here, but what? %s \n Status is %d \n\n", result, status);

            exit(1);

        }

        else 

                {

           wait(&status);

           printf("Something else happened here %s \n Status after wait is %d", command, status);

           if (status != 0)

                printf("And something happened again? \n");

        }   

        result = strtok( NULL, delims );

    } 

}

The entire pid-fork-&status structure is just too vague for me, can anyone explain what happens on every step of the way?

Using execl, by the way, worked for me, but I have to use execv.

Thanks

Structures in functions.

Soileau — Mon, 23 Nov 2009 16:46:27 GMT

I am trying to write a function to add two arrays. The catch is that the arrays have to parts of a structure. So here is what I have so far:

#include 



struct poly {

        array1[];

        array2[];

        length;

        };



void polyadd(int array1[],int array2[],int length) {      

        int i;

        struct poly p;

        for(i=0;i
                p.array1[i]=array1[i] + array2[i];

                printf(" %d ", p.array1[i]);

        }

}



int main(void) {

        struct poly name1;

        name1.length = 4;

        name1.array1[4] = {3,0,7};

        name1.array2[4] = {0,15,0,-4};

        polyadd(name1.array1,name1.array2,name1.length);

        return 0;

}

And here are the error messages I am getting:

structadd.c:4: error: expected specifier-qualifier-list before âarray1â
structadd.c: In function âpolyaddâ:
structadd.c:13: error: âstruct polyâ has no member named âarray1â
structadd.c:14: error: âstruct polyâ has no member named âarray1â
structadd.c: In function âmainâ:
structadd.c:20: error: âstruct polyâ has no member named âlengthâ
structadd.c:21: error: âstruct polyâ has no member named âarray1â
structadd.c:21: error: expected expression before â{â token
structadd.c:22: error: âstruct polyâ has no member named âarray2â
structadd.c:22: error: expected expression before â{â token
structadd.c:23: error: âstruct polyâ has no member named âarray1â
structadd.c:23: error: âstruct polyâ has no member named âarray2â
structadd.c:23: error: âstruct polyâ has no member named âlengthâ

Passing an array of structs by reference?

neithan — Mon, 23 Nov 2009 16:10:28 GMT

Hi, i'm just mixing file handling and struct types and pointers to learn, but i'm a little stuck on this.
I might be doing something awfull i can tell, sorry for that. Can anyone help? What's the best way to pass

#include 

#include 

#include 

#include 



struct persona {

    char nombre[15];

    char apellido[15];

    unsigned edad;

};



int edadMedia(struct persona *);



int main()

{

    char *filename = "C:\\Usuarios\\Administrador\\Escritorio\\C\\test.txt";

    printf("Accediendo a %s:\n", filename);

    FILE *file = fopen(filename, "r");



    struct persona nombres[10];

    int counter = 0, contador = 0;

    char *linea;

    linea = malloc(15 * sizeof(char));



    while((fgets(linea, 15, file)) && *linea != EOF)

    {

        printf("Reading line %i -> %s", counter, linea);

        if(linea[0] == '#') continue;

        switch (counter)

        {

            case 0:

                strcpy(nombres[contador].nombre, linea);

                counter++;

                break;

            case 1:

                strcpy(nombres[contador].apellido, linea);

                counter++;

                break;

            case 2:

                nombres[contador].edad = (unsigned int) atoi(linea);

                counter = 0;

                contador++;

                break;

        }

    }

    printf("\n\n\t[i] Detectados %i miembros!\n", contador);

    printf("\t[i] Edad media %i años", edadMedia(nombres));

    return 0;

}



int edadMedia(struct persona * nombres) { //code still to go here }

Multiple simultaneous file open in C

SimonLeefe — Mon, 23 Nov 2009 13:10:48 GMT

I have an arbitrary number of files whose names I will know and I want to open them for reading. The important point is that I do not want to open them sequentially using a single file pointer. I need to have them all open at the same time. This suggests using and an array of file pointers, where this is declared to be of dimension N, where N is the maximum number of files I can have open.

A quick trawl of the web has not brought anything up and it's not in my textbooks. Being a relatively infrequent C-programmer, I'm not at all sure about setting up and using arrays of file pointers. What is the declaration syntax and how is it used? (Or is there another/better way to do what I want?)

Using pcap, dirent.h and error C2085, C2061

hjazz — Mon, 23 Nov 2009 09:31:45 GMT

Hi all,

I'm new to using Visual Studio. I'm currently using VS .NET 2003 on Vista, and I'm trying to port a program from Linux to Windows.

The program uses the pcap library. I have installed WinPcap 4.0.2 and downloaded the Developer's Pack WpdPack_4_0_2. However, I have no idea what to do with the developer's pack, i.e. what do I do with the pcap.h and other header files/libraries so my program can use the pcap functions.

Also, one of the errors I've gotten was that the file dirent.h cannot
be found. Is there some way to workaround this problem, i.e. some
library that I can download and use so I don't have to change my code? If not, what are the alternatives?

Lastly, I seem to get a lot of syntax errors. The program was able to
compile and run without errors in Linux. One of these errors are
"error C2085: '': not in formal parameter list." These errors occur in the header file which is in the following format:

#ifndef HEADER_H

#define HEADER_H



/* Bunch of #include and #define statements */

/* Struct declarations */



/* Here's where the errors are */

static void *Function1(int n);

int Function2(ABC *x);  //ABC is a self-defined structure declared in

this header file

ABC *Function3(void *a);

static inline void Function4(unsigned char *c, unsigned char *d, int

e);



/* There is also a C2061: syntax error: identifier 'inline' for the

following line */

inline int Function5(ABC *x, unsigned char *f, int g);



#endif

Please advise.

Thank you.

Regards,
Rayne

Emulating GREP and SED with C?

Mattpd — Mon, 23 Nov 2009 05:53:39 GMT

I have written some bash shell scripts, using grep and sed. Are there any functions in C that do something similar to grep and mainly sed? I need to be able to edit and delete individual lines of text in an external txt file, based on user input.

IPv6 Client Server Problem

shahab.burki — Sun, 22 Nov 2009 23:09:53 GMT

Hi,

I am trying to develop a small IPv6 application in C. I am stuck at server side. GCC issues the error while call to ACCEPT function "socket function on non-socket". Can anyone help me?

1. Client Code

#include "shahab.h"







int main(int argc, char **argv){



   int connectSocket;

   int numberOfBytes;

   char recvData[MAX_SIZE];

   int yes=1;



   struct sockaddr_in6 serverAddress;

   

   if(argc!=2){

    

     perror("Command Line Arguments");

     exit(1);

    }



    if((connectSocket=socket(AF_INET6,SOCK_STREAM,0))<0){



      perror("socket error");

      exit(1);

    }



    bzero(&serverAddress, sizeof(serverAddress));



    serverAddress.sin6_family=AF_INET6;

    serverAddress.sin6_port=htons(SERVER_A_PORT);

    

    if(inet_pton(AF_INET6,argv[1],&serverAddress.sin6_addr)<=0){



        perror("Server Address");

        exit(1);

    }



    if(connect(connectSocket,(struct sockaddr*)&serverAddress,sizeof(serverAddress))<0){



      perror("connect error");

      exit(1);

   }



  for(;;){



    numberOfBytes=read(connectSocket,recvData,MAX_SIZE);



    if(numberOfBytes<0){



    perror("Recv Error");

    exit(1);



    }



    recvData[numberOfBytes]='\0';



    printf("Received : %s\n",recvData);





  }







  close(connectSocket);





  printf("I am in IPv6 Client\n");



  return 0;







}

2. Server Code

#include "shahab.h"



int main(){



  int listenSocket;

  int connectSocket;

  int numberOfBytes;

  int yes=1;

  char recvData[MAX_SIZE];

  char ip6[INET6_ADDRSTRLEN];

  socklen_t sin_size;







  struct sockaddr_in6 serverAddress;

  struct sockaddr_in6 clientAddress;



  if(listenSocket=socket(AF_INET6,SOCK_STREAM,0)<0){



    perror("Connect Problem");



  }



 /* if(setsockopt(listenSocket,SOL_SOCKET, SO_REUSEADDR, &yes,sizeof(int))==-1){



    perror("Sock Option Problem");

    exit(1);

  }*/



  bzero(&serverAddress,sizeof(serverAddress));



  serverAddress.sin6_family=AF_INET6;

  serverAddress.sin6_addr=in6addr_any;

  serverAddress.sin6_port=htons(SERVER_A_PORT);



  bind(listenSocket,(struct sockaddr*)&serverAddress,sizeof(serverAddress));



  



  listen(listenSocket,BACKLOG);



  for(;;){



        

        sin_size=sizeof serverAddress;

        connectSocket= accept(listenSocket, (struct sockaddr *)&clientAddress, &sin_size);



        if(connectSocket==-1){

                

                perror("Problem");

        }

         

       /* inet_ntop(AF_INET6, &(clientAddress.sin6_addr), ip6, INET6_ADDRSTRLEN);

        printf("The address is: %s\n", ip6);*/





        send(connectSocket, "Hello World from Server\n", MAX_SIZE, 0);



        close(connectSocket);



        }



  





        





  printf("I am IPv6 Server\n");

  return 0;

}

Thanks

can someone help me to make long programs short I've got no Idea please help!

markeen — Sun, 22 Nov 2009 13:24:20 GMT

#include

#include



int main()

{

        int x[5], y[5], z[5], i, d;

        

        for(i=0;i<5;i++)

        {

                printf("Enter int%d: ", i);

                scanf("%d", &x[i]);

        }

                

        if((x[0]>x[1]) && (x[0]>x[2]) && (x[0]>x[3]) && (x[0]>x[4]))

        {

                y[0]=x[0];

                

                if((x[1]>x[2]) &&( x[1]>x[3]) &&(x[1]>x[4]))

                {

                        y[1]=x[1];

                        

                        if((x[2]>x[3])&&(x[2]>x[4]))

                        {

                                y[2]=x[2];

                                

                                if((x[3]>x[4]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[3]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[3];

                                }

                        }

                        else if((x[3]>x[2])&&(x[3]>x[4]))

                        {

                                y[2]=x[3];

                                

                                if((x[2]>x[4]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[2]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[4]>x[2])&&(x[4]>x[3]))

                        {

                                y[2]=x[4];

                                

                                if((x[2]>x[3]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[2]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[2];

                                }

                        }

                }

                else if((x[2]>x[1]) &&( x[2]>x[3]) &&(x[2]>x[4]))

                {

                        y[1]=x[2];

                        

                        if((x[1]>x[3])&&(x[1]>x[4]))

                        {

                                y[2]=x[1];

                                

                                if((x[3]>x[4]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[3]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[3];

                                }

                        }

                        else if((x[3]>x[1])&&(x[3]>x[4]))

                        {

                                y[2]=x[3];



                                if((x[1]>x[4]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                                else if((x[4]>x[1]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[4]>x[1])&&(x[4]>x[3]))

                        {

                                y[2]=x[4];

                                

                                if((x[1]>x[3]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[1]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[1];

                                }

                        }

                }

                else if((x[3]>x[1]) &&( x[3]>x[2]) &&(x[3]>x[4]))

                {

                        y[1]=x[3];

                        

                        if((x[1]>x[2])&&(x[1]>x[4]))

                        {

                                y[2]=x[1];



                                if((x[2]>x[4]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[3];

                                }

                                else if((x[4]>x[2]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[2]>x[1])&&(x[2]>x[4]))

                        {

                                y[2]=x[2];



                                if((x[1]>x[4]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[1]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[4]>x[1])&&(x[4]>x[2]))

                        {

                                y[2]=x[4];

                                

                                if((x[1]>x[2]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[1]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[1];

                                }

                        }

                }

                else if((x[4]>x[1]) &&( x[4]>x[2]) &&(x[4]>x[3]))

                {

                        y[1]=x[4];

                        

                        if((x[1]>x[2])&&(x[1]>x[3]))

                        {

                                y[2]=x[1];



                                if((x[2]>x[3]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[2]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[2]>x[1])&&(x[2]>x[3]))

                        {

                                y[2]=x[2];



                                if((x[1]>x[3]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[1]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[3]>x[1])&&(x[3]>x[2]))

                        {

                                y[2]=x[3];



                                if((x[1]>x[2]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[1]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[1];

                                }

                        }

                }

        }

        

        else if((x[1]>x[0])&&(x[1]>x[2])&&(x[1]>x[3])&&(x[1]>x[4]))

        {

                y[0]=x[1];

                

                if((x[0]>x[2]) &&( x[0]>x[3]) &&(x[0]>x[4]))

                {

                        y[1]=x[0];

                        

                        if((x[2]>x[3])&&(x[2]>x[4]))

                        {

                                y[2]=x[2];

        

                                if((x[3]>x[4]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[3]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[3];

                                }

                        }

                        else if((x[3]>x[2])&&(x[3]>x[4]))

                        {

                                y[2]=x[3];



                                if((x[2]>x[4]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[2]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[4]>x[2])&&(x[4]>x[3]))

                        {

                                y[2]=x[4];



                                if((x[2]>x[3]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[2]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[2];

                                }

                        }

                }

                else if((x[2]>x[0]) &&( x[2]>x[3]) &&(x[2]>x[4]))

                {

                        y[1]=x[2];

                        

                        if((x[0]>x[3])&&(x[0]>x[4]))

                        {

                                y[2]=x[0];



                                if((x[3]>x[4]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[3]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[3];

                                }

                        }

                        else if((x[3]>x[0])&&(x[3]>x[4]))

                        {

                                y[2]=x[3];

                                

                                if((x[0]>x[4]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[0]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[4]>x[0])&&(x[4]>x[3]))

                        {

                                y[2]=x[4];

                                

                                if((x[0]>x[3]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[0]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[0];

                                }

                        }

                        

                }

                else if((x[3]>x[0]) &&( x[3]>x[2]) &&(x[3]>x[4]))

                {

                        y[1]=x[3];



                        if((x[0]>x[2])&&(x[0]>x[4]))

                        {

                                y[2]=x[0];

                                

                                if((x[2]>x[4]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[2]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[2]>x[0])&&(x[2]>x[4]))

                        {

                                y[2]=x[2];



                                if((x[0]>x[4]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[0]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[4]>x[0])&&(x[4]>x[2]))

                        {

                                y[2]=x[4];



                                if((x[0]>x[2]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[0]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[0];

                                }

                        }

                }

                else if((x[4]>x[0]) &&( x[4]>x[2]) &&(x[4]>x[3]))

                {

                        y[1]=x[4];

                        

                        if((x[0]>x[1])&&(x[0]>x[2]))

                        {

                                y[2]=x[0];



                                if((x[1]>x[2]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[1]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[1]>x[0])&&(x[1]>x[2]))

                        {

                                y[2]=x[1];



                                if((x[0]>x[2]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[0]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[2]>x[0])&&(x[2]>x[1]))

                        {

                                y[2]=x[2];



                                if((x[0]>x[1]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[1];

                                }

                                else if((x[1]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[0];

                                }

                        }

                }

        }

        

        else if((x[2]>x[0])&&(x[2]>x[1])&&(x[2]>x[3])&&(x[2]>x[4]))

        {

                y[0]=x[2];

                

                if((x[0]>x[1]) &&( x[0]>x[3]) &&(x[0]>x[4]))

                {

                        y[1]=x[0];

                        

                        if((x[1]>x[3])&&(x[1]>x[4]))

                        {

                                y[2]=x[1];



                                if((x[3]>x[4]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[3]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[3];

                                }

                        }

                        else if((x[3]>x[1])&&(x[3]>x[4]))

                        {

                                y[2]=x[3];



                                if((x[1]>x[4]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[1]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[4]>x[1])&&(x[4]>x[3]))

                        {

                                y[2]=x[4];

                                

                                if((x[1]>x[3]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[1]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[1];

                                }

                        }

                }

                else if((x[1]>x[0]) &&( x[1]>x[3]) &&(x[1]>x[4]))

                {

                        y[1]=x[1];



                        if((x[0]>x[3])&&(x[0]>x[4]))

                        {

                                y[2]=x[0];

                                

                                if((x[3]>x[4]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[3]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[3];

                                }

                        }

                        else if((x[3]>x[0])&&(x[3]>x[4]))

                        {

                                y[2]=x[3];



                                if((x[0]>x[4]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[0]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[4]>x[0])&&(x[4]>x[3]))

                        {

                                y[2]=x[4];

                                

                                if((x[0]>x[3]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[0]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[0];

                                }

                        }

                }

                else if((x[3]>x[0]) &&( x[3]>x[1]) &&(x[3]>x[4]))

                {

                        y[1]=x[3];



                        if((x[0]>x[1])&&(x[0]>x[4]))

                        {

                                y[2]=x[0];



                                if((x[1]>x[4]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[1]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[1]>x[0])&&(x[1]>x[4]))

                        {

                                y[2]=x[1];



                                if((x[0]>x[4]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[0]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[4]>x[0])&&(x[4]>x[1]))

                        {

                                y[2]=x[4];

                                

                                if((x[0]>x[1]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[1];

                                }

                                else if((x[1]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[0];

                                }

                        }

                }

                else if((x[4]>x[0]) &&( x[4]>x[1]) &&(x[4]>x[3]))

                {

                        y[1]=x[4];

                        if((x[0]>x[1])&&(x[0]>x[3]))

                        {

                                y[2]=x[2];

                                

                                if((x[1]>x[3]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[1]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[1]>x[0])&&(x[1]>x[3]))

                        {

                                y[2]=x[3];



                                if((x[0]>x[3]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                        }

                        else if((x[3]>x[0])&&(x[3]>x[1]))

                        {

                                y[2]=x[4];

                                

                                if((x[0]>x[1]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[1];

                                }

                                else if((x[1]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[0];

                                }

                        }

                }

        }

        

        else if((x[3]>x[0])&&(x[3]>x[1])&&(x[3]>x[2])&&(x[3]>x[4]))

        {

                y[0]=x[3];

                

                if((x[0]>x[1]) &&( x[0]>x[2]) &&(x[0]>x[4]))

                {

                        y[1]=x[0];



                        if((x[1]>x[2])&&(x[2]>x[4]))

                        {

                                y[2]=x[1];



                                if((x[2]>x[4]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[2]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[2]>x[1])&&(x[2]>x[4]))

                        {

                                y[2]=x[2];



                                if((x[1]>x[4]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[1]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[4]>x[1])&&(x[4]>x[2]))

                        {

                                y[2]=x[4];

                                

                                if((x[1]>x[2]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[1]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[1];

                                }

                        }

                }

                else if((x[1]>x[0]) &&( x[1]>x[2]) &&(x[1]>x[4]))

                {

                        y[1]=x[1];

                        

                        if((x[0]>x[2])&&(x[0]>x[4]))

                        {

                                y[2]=x[0];



                                if((x[2]>x[4]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[2]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[2]>x[0])&&(x[2]>x[4]))

                        {

                                y[2]=x[2];



                                if((x[0]>x[4]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[0]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[4]>x[0])&&(x[4]>x[2]))

                        {

                                y[2]=x[4];



                                if((x[0]>x[2]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[0]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[0];

                                }

                        }

                }

                else if((x[2]>x[0]) &&( x[2]>x[1]) &&(x[2]>x[4]))

                {

                        y[1]=x[2];



                        if((x[0]>x[1])&&(x[0]>x[4]))

                        {

                                y[2]=x[0];



                                if((x[1]>x[4]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[1]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[1]>x[0])&&(x[1]>x[4]))

                        {

                                y[2]=x[1];



                                if((x[0]>x[4]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[4];

                                }

                                else if((x[4]>x[0]))

                                {

                                        y[3]=x[4];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[4]>x[0])&&(x[4]>x[1]))

                        {

                                y[2]=x[4];

                                

                                if((x[0]>x[1]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[1];

                                }

                                else if((x[1]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[0];

                                }

                        }

                }

                else if((x[4]>x[0]) &&( x[4]>x[1]) &&(x[4]>x[2]))

                {

                        y[1]=x[4];



                        if((x[0]>x[1])&&(x[0]>x[2]))

                        {

                                y[2]=x[0];

                                if((x[1]>x[2]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[1]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[1]>x[0])&&(x[1]>x[2]))

                        {

                                y[2]=x[1];

                                if((x[0]>x[2]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[0]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[2]>x[0])&&(x[2]>x[1]))

                        {

                                y[2]=x[2];

                                if((x[0]>x[1]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[1];

                                }

                                else if((x[1]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[0];

                                }

                        }

                }

        }

        

        else if((x[4]>x[0])&&(x[4]>x[1])&&(x[4]>x[2])&&(x[4]>x[3]))

        {

                y[0]=x[4];



                if((x[0]>x[1]) &&( x[0]>x[2]) &&(x[0]>x[3]))

                {

                        y[1]=x[0];



                        if((x[1]>x[2])&&(x[1]>x[3]))

                        {

                                y[2]=x[1];



                                if((x[2]>x[3]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[2]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[2]>x[1])&&(x[2]>x[3]))

                        {

                                y[2]=x[2];



                                if((x[1]>x[3]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[1]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[3]>x[1])&&(x[3]>x[2]))

                        {

                                y[2]=x[3];



                                if((x[1]>x[2]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[1]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[1];

                                }

                        }

                }

                else if((x[1]>x[0]) &&( x[1]>x[2]) &&(x[1]>x[3]))

                {

                        y[1]=x[1];

                        

                        if((x[0]>x[2])&&(x[0]>x[3]))

                        {

                                y[2]=x[0];

                

                                if((x[2]>x[3]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[2]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[2];

                                }

                        }

                        else if((x[2]>x[0])&&(x[2]>x[3]))

                        {

                                y[2]=x[2];

                        

                                if((x[0]>x[3]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[0]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[3]>x[0])&&(x[3]>x[2]))

                        {

                                y[2]=x[3];

                

                                if((x[0]>x[2]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[0]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[0];

                                }

                        }

                }

                else if((x[2]>x[0]) &&( x[2]>x[1]) &&(x[2]>x[3]))

                {

                        y[1]=x[2];



                        if((x[0]>x[1])&&(x[0]>x[3]))

                        {

                                y[2]=x[0];



                                if((x[1]>x[3]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[1]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[1]>x[0])&&(x[1]>x[3]))

                        {

                                y[2]=x[1];

                        

                                if((x[0]>x[3]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[3];

                                }

                                else if((x[3]>x[0]))

                                {

                                        y[3]=x[3];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[3]>x[0])&&(x[3]>x[1]))

                        {

                                y[2]=x[3];

                

                                if((x[0]>x[1]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[1];

                                }

                                else if((x[1]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[0];

                                }

                        }

                }

                else if((x[3]>x[0]) &&( x[3]>x[1]) &&(x[3]>x[2]))

                {

                        y[1]=x[3];

                        

                        if((x[0]>x[1])&&(x[0]>x[2]))

                        {

                                y[2]=x[0];



                                if((x[1]>x[2]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[1]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[1];

                                }

                        }

                        else if((x[1]>x[0])&&(x[1]>x[2]))

                        {

                                y[2]=x[1];

                

                                if((x[0]>x[2]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[2];

                                }

                                else if((x[2]>x[0]))

                                {

                                        y[3]=x[2];

                                        y[4]=x[0];

                                }

                        }

                        else if((x[2]>x[0])&&(x[2]>x[1]))

                        {

                                y[2]=x[2];

                

                                if((x[0]>x[1]))

                                {

                                        y[3]=x[0];

                                        y[4]=x[1];

                                }

                                else if((x[1]>x[0]))

                                {

                                        y[3]=x[1];

                                        y[4]=x[0];

                                }

                        }

                }

        }



        printf("\n%d  %d  %d\n", x[0],y[4],z[0]=y[0]);

        printf("%d  %d  %d\n", x[1],y[3],z[1]=y[1]);

        printf("%d  %d  %d\n", x[2],y[2],z[2]=y[2]);

        printf("%d  %d  %d\n", x[3],y[1],z[3]=y[3]);

        printf("%d  %d  %d\n", x[4],y[0],z[4]=y[4]);

        printf("\n\nHighest = %d\n", y[0]);

        printf("Lowest = %d\n", y[4]);

}

Please help. Memory Management Error

Rsh>>> — Sun, 22 Nov 2009 11:35:48 GMT

/* This program returns a run time error as follows: "Your code has stopped its execution with a non-zero (failure) exit value.This is generally due to run time Exceptions like Memory Access Violation and Floating Point Exception. Please check your code for run time Exceptions and try again." PLEASE HELP.*/



#include

#include

struct amicable

{

int **amicablePairs;

int size;

};

struct amicable* getAmicablePairs(int startnum,int endnum);

int main()

{

struct amicable *ami;

int i,startnum,endnum;

clrscr();



ami=getAmicablePairs(100,2000);

printf("{");

for(i=0;isize;i++)

{

printf("{%d %d}",ami->amicablePairs[i][0],ami->amicablePairs[i][1]);

}

printf("}");

getch();

return 0;

}





struct amicable * getAmicablePairs(int startnum,int endnum)

{

struct amicable *amic;

int i,j,divisor=0,divisor1=0,k=0,l,**p;

p=malloc(15*sizeof(int*));

if(p==NULL)

printf("failed for p");

if(startnum>0&&endnum>0&&startnum
{

for(i=startnum;i<=endnum;i++)

{

for(j=1;j<=i/2;j++)

{

if(i%j==0)

divisor+=j;

}

if(divisor<=endnum&&divisor>i)

{

for(l=1;l<=divisor/2;l++)

{

if(divisor%l==0)

divisor1+=l;

}

if(divisor1==i)

{

p[k]=malloc(2*sizeof(int));

if(p[k]==NULL)

printf("failed for loop");

p[k][0]=i;p[k][1]=divisor;

//amic->amicablePairs[k][0]=i;

//amic->amicablePairs[k][1]=divisor;

k++;

}

}

divisor=0;divisor1=0;

}

if(k==1)

goto here;

amic->size=k;

amic->amicablePairs=p;

return amic;

}

else

here:return NULL;

}

Need to Fix this

nhamyl — Sun, 22 Nov 2009 09:35:54 GMT

this program has information about customers. this program has to perform the following functions.
- display list of all customers
- search by name
- search by id
- display list of customers having credit limit above 5000
- add new customers

i am unable to compile the program. here are the codes. can anyone fix it?

#include 

#include 

#include 

#define MAX=999

int i;

int id;



struct customer {

 char custID[20];

 char name[50];

 char address[80];

 char tell[15];

 float credl; 

};

int add_Name ();

int menu_Display ();

int get_Menu ();

int get_Option ();

int cust_id();

 int cust_Name();





int main()

{

    

    menu_Display ();

    get_Menu ();

    get_Option ();

    

    getch();

 return 0;

 

}

int menu_Display () {

     int choice=0;

     while (choice!=6) {

           get_Menu ();

           choice = get_Option();

           }}

int get_Menu (){

    int i;

    for (i=0; i<1; i++) {

    printf ("\t1. Display information of all customers\n\n");

    printf ("\t2. Search for customer by Name\n\n");

    printf ("\t3. Search for customer by ID\n\n");

    printf ("\t4. Display a list of customers having credit limit above 5,000\n\n");

    printf ("\t5. Add new customer\n\n");

    printf ("\t6. Exit\n\n");

}

    

}

int get_Option () {

    

    int option;

    printf ("Please enter your option...");

    scanf ("%d", &option);

}

int menu_Option (int option) {

    int i;

    switch (option) {

           case 1 : cust_Name();

           break;

           case 2 : cust_id();

           break;

           case 3 : add_Name();

           break;

           case 6 : printf("The program will now exit\n");

           break;

           default : printf ("Sorry that does not exist");

           i=getchar();

           break;

           }

           }





int add_Name () {

 int i;

 struct customer xrecord[200];

 for (i=0;i<1;i++)

 {

  strcpy(xrecord[i].custID,"ID00");

  //strcpy(xrecord[i].custID,(strcat(xrecord[i].custID,i));

  printf("Enter Name:");

  scanf("\n%s",&(xrecord[i].name)) ;

  printf("Enter address:");

  printf ("\n");

  scanf("\n%s",&(xrecord[i].address));

  printf("Enter tell:");

  scanf("\n%s",&(xrecord[i].tell));

  printf("Enter credl:"); 

  scanf("\n%f",&(xrecord[i].credl));

  

}

  

 }

 int cust_Name() {

    int match;

    int i;

    int result;

    int loop=0;

    char name[20];

    

    printf("Please enter the name which you are searching for\n");

    gets(name);

    while (match == 0 && i < MAX) {

          result= strcmp(all_names[loop].name,name);

          loop++;

          }

          if (loop == MAX) {

                   printf ("Match not found\n");

                   }

          i=getchar();

          }

 int cust_id() {

    int match;

    int i;

    int result=0;

    int loop=0;

    int id;

    

    printf ("Please enter the id number which you are searching for\n");

    scanf ("%d", &id);

    while (match == 0 && i< MAX) {

          result = strcmp (all_names[loop].id,id);

          loop++;

          }

          if (loop == MAX) {

                   printf ("Match not found");

                   }

          i = getchar();

          }

dynamic array

cmsc — Sun, 22 Nov 2009 06:52:18 GMT

I want to make a dynamic array. but when I view the array, I think there's something wrong with the index part. Please help. Thanks!

here's my code:

#include





main(){



        int* a;

        int number;

        int choice;

        int index = 0;

        int head;

        

        

        while(choice!=4){

        

                printf("\tMENU\t\n");

                printf("[1] add number to array\n");

                printf("[2] view array\n");

                printf("[3] search using linear search\n");

                printf("[4] quit program\n");

                scanf("%d", &choice);

                

                switch(choice){

                        case 1: head = add(&index, a);

                                        break;

                        

                        case 2:head = view(&index,a);

                                        break;

                                        

                        //case 3:linsearch(&index,array[5]);

                                        //break;

                                        

                        case 4: return;

                                        break;

                                        

                        default: printf("invalid input!!!\n");

                        

                }

}

}



 int add(int* index, int* a){

        

        int number;

        int i;

        

                printf("enter number you want to enter in the array.\n");

                scanf("%d", &number);

                

                *a = (int) malloc (5*sizeof(int));

                

                for(i = 0; i <= *index; i ++){

                        a[i] = number;

                }

                

                return *index;

}



 view(int* index, int* a){



        int i; 

        printf("\n");

        

                for(i = 0; i <= *index; i++){

                        printf("index: %d, %d ", *index, a[i]);

                }

                printf("\n\n");

                

                return a[5];

}

Scheduler

Cmad — Sun, 22 Nov 2009 05:18:36 GMT

Iam currently working on the design of preemptive scheduler iln Borland C. I want to know about the use of interrupts and timers in Borland C for preempting the task. Just clue of upgrading about them is enough.

How to color some text in Dev C

DoEds — Sun, 22 Nov 2009 03:45:56 GMT

#include 

#include 



#define SIZE 31



int main()

{

     int array[SIZE]={0};

     int i,j;

     int startDay=0,numDays=30;

     

     printf("  S   M    T    W    TH    F    S\n");

     

     for (i=1;i<=1+ startDay*5;i++)

     printf(" ");

     

     for (i= 1; i <= numDays; i++) 

     {

               

               printf("%2d",i);

               if ((i+startDay)%7 > 0)        

                {    printf("   ");

                   system("color 6");}

                    

               else  

                    printf("\n ");

     }

     startDay = (startDay + numDays)%7;

     

     

     

            

     

     

     getchar();

     getchar();

}

I used

system("color ");

but it will only colorize my enter text...
I only want to colorize the days in Sunday;

I dont know how to do it...Can anyone teach me please?.,

Converting long integer Into Array

dieom — Sat, 21 Nov 2009 17:05:11 GMT

What I am trying to accomplish here is to split a long integer apart so I can look at its first, last, and center digits. What I am currently using is this:

int main() {

  long i, t[1024];

  

  i = 100;



  while (i < 150) {

    t = i; // My attempt at converting the long into an array.

    printf("%ld\n", t[2]);

    i += 1;

  }

Any help would be appreciated!

FILE stream, syntax in getc

neithan — Sat, 21 Nov 2009 15:38:39 GMT

Hi everyone, i have this portion of code

while(c = getc(file) != EOF)

c is an int and file is a FILE *file = fopen(filename, "r");

The filename points to a file with 2 lines, 10 characters total. That while always makes c a value of 1 (accodring to ASCII -> start text, dunno what that mean).
But when i use this while:

while((c = getc(file)) != EOF)

It works perfect. I though that was equivalent...i'm missing something on basic syntax here. What's wrong in the first while?

Thank you.

char in c?

dewdropz — Sat, 21 Nov 2009 10:32:32 GMT

hi, i am new to c have to write a program to check the shape.
I think the error is somewhere at shape= square. I know i can use printf statements but i want it in this format. Can someone help me please?

#include 

int main (void)

{

int length,breadth;

char shape;

printf("Input your length: ");

scanf("%f", &length);

printf("Input your breadth: ");

scanf("%f", &breadth);



if (length=breadth)

       { 

            shape= 'square';      

       } 

else {

            shape = 'rectangle'

        }

printf(" the length is%d, breadth is %d , hence given shape is %s", length, breadth, shape);

Need help to create matrix

rahul.nutron — Sat, 21 Nov 2009 06:54:14 GMT

I have to create a matrix in c from microarray data that so I have to read each string line wise and compare they are related or not. help me....***

Error in simple C menu

Mattpd — Sat, 21 Nov 2009 06:21:58 GMT

If I run the program, and select q, it will quit correctly. If I select e it goes to the edit menu but prints it twice. If I then select q it goes to the main menu and prints the default case, "please select from menu", then prints the main menu again. If I select q now, it goes to the edit menu, not quitting the program like it did before. So now it's stuck in a loop between main and edit when I select q.

#include   

#include 



void edit(void){



printf ("\nEDIT MENU\n");

printf ("  (a)Add\n");

printf ("  (p)Display\n");

printf ("  (i)Reutrn\n");

printf ("  (o)Check Out\n");

printf ("  (d)Delete\n");

printf ("  (q)Main Menu\n");





char choice;

scanf ("%c",&choice); 



switch (choice) {



case 'a':

  system("./add");

  break;

  



case 'p':

  system("./display");

  break;



case 'i':

  system("./return");

  break;



case 'o':

  system("./checkout");

  break;



case 'd':

  system("./delete");

  break;



case 'q':

  main();



default:

  edit();



}



}



void reports(void)

{



}



void add(void)

{

}



void del(voi)

{

}



int main(void){



        

printf ("MAIN MENU\n");

printf ("  (e)Edit\n");

printf ("  (r)Reports\n");

printf ("  (q)Quit\n");



char choice;

scanf ("%c",&choice); 



switch (choice) {

  case 'e':

  edit();

  break;

  

  

  case 'r':

  reports();

  break;

  



  case 'q':

  break;



  default: 

  printf("Choose from the menu\n");

  main();

}

return 0;

}

Converting this SH script to C (not .

Mattpd — Sat, 21 Nov 2009 03:40:42 GMT

In the title I was going to write (not C script) but they are essentially the same I think. My bad, anyway...

I recently wrote a some SH scripts to manage lines of text in a separate txt file. Now my new assignment is to convert the whole thing to C. Any ideas on how to convert these lines to C?

grep -w "^$npname.*" parts.txt

echo $npname:$noname:in >> parts.txt

 sed '/'^"$npname":'/d' parts.txt > parts.tmp

 

 mv parts.tmp parts.txt

how to use the local variable form one function to other function

thebluestar — Sat, 21 Nov 2009 02:21:55 GMT

Here is the problem:write in saparate function without using global variable
1/(function input)enter N in the range [0,20], then enter N numbers
2/(function display)Display N numbers in 2 columns
Here is my source code

#include

#include

void Input(int *p,int n)

{

    int i;

    do

    {

     printf("Enter N numbers u want to input: ");

     scanf("%d",&n); 

    }while ( (n<0) || (n>20) );

    p =(int *)malloc(n*sizeof(int));

    printf("Ennter %d numbers: ",n);

    for( i=0; i
    {

         printf("\nNumber%: ",i);

         scanf("%d",p+i);

    }

    

}



void Display(int *p, int n)

{

     int i;

     printf("test");

     for( i=0; i
     {

        printf(" %d",p[i]);  

     }

}



int main()

{

  int *a, *N;

  Input(a,&N);

  Display(a,&N);

  getch();

  return 0;

}

I don't know how can I use the variable N in function input for the next function.

memcpy with int clears entire buffer

cmk2901 — Sat, 21 Nov 2009 00:21:09 GMT

Hi,

I have a char* buffer that is 1024 bytes in size, and am trying to write an int to a particular offset in the buffer, in this case 0, but all offsets have the same problem.

I initialize the buffer to some values when I first start up. For example, the first 8 bytes contain two separate ints, followed by 2 chars. When I print this out, it shows up as full.

However, when I try to add another value as shown in the code below, it completely destroys all the other data in the buffer.

char* buffer = new char[1024];



***buffer initialization code***



int fd = 4;

int bufferOffset = 0;



memcpy(buffer + bufferOffset, &fd, 4);



cout << buffer << endl;

Does anyone know why this could be happening? I'm under the impression that the above code should copy the 4 bytes of an int to my buffer, not completely destroy it.

Pixel Count

cokacola — Fri, 20 Nov 2009 18:44:43 GMT

The purpose of the program is to take a position and count how many "pixels" are in the "blob". If there is no "pixel" aka the value is 0, the blob number is 0. If there is a pixel, the blob_check function recursively checks the surrounding cells for "pixels" aka values of 1. My program compiles but doesn't accurately count the number of pixels in the blob. Please help!

#include 

#include 



int blob_check(int tab[][], int x, int y);



#define N 5



int main(int argc, char *argv[])

{

        int x,y,i,j;

        int row=0;

        char line[80];

        int table[N][N] = { {1,1,0,0,0},

                                                {0,1,1,0,0},

                                                {0,0,1,0,1},

                                                {1,0,0,0,1},

                                                {0,1,0,1,1}};

                                

        printf("\t0\t1\t2\t3\t4\t");

        printf("\n   -----------------------------------------");                        

        for(i=0;i<5;i++)

        {

                printf("\n   |\n%d  |\t", i);

                for(j=0;j<5;j++)

                {

                        printf("%d\t", table[i][j]);

                }

        }

                                                                

                                                                

        printf("\n\nEnter x-y coordinates of cell  => ");

        scanf("%d %d", &x, &y);                                                                

        

        printf("Pixel quantity in blob: %i\n", blob_check(table, x, y));

        

        system("pause");

        return 0;

}



int blob_check(int pic[N][N], int x, int y)

{

        if (pic[x][y] == 0)

                return 0;

        else

        {

                pic[x][y] = 0;

                

                int sum = 1;

                

                //check 

                if (x>0)

                {

                        sum += blob_check(pic, x-1, y);

                        if (y
                                sum += blob_check(pic, x-1, y+1);

                }

                else if (y
                {

                        sum += blob_check(pic, x, y+1);

                        if (x
                                sum += blob_check(pic, x+1, y+1);

                }

                else if (x
                {

                        sum += blob_check(pic, x+1, y);

                        if (y>0)

                                sum += blob_check(pic, x+1, y-1);

                }                

                else if (y>0)

                {

                        sum += blob_check(pic, x, y-1);

                        if (x>0)

                                sum += blob_check(pic, x-1, y-1);

                }



                return sum;

        }

}

C program for to find optimal path

kirtics344 — Fri, 20 Nov 2009 15:42:07 GMT

Time limit : 10 secs. (The program must produce output for all test cases within the stipulated time)

A spaceship carrying a convention of high ranking officials had a close shave with a meteor. They are now scattered over the surface over a meteor and the spaceship is beyond repair.
Fluke LandCrawler was an emergency replacement for a space rescue mission in the distant galaxy Alfa-Bentauri. You are KHAL – the computer on the land-Rover carrying Fluke. He needs to rescue as many survivors as possible but can’t figure out the best path. Fluke lied about his CompSc. Degree to get in to SpaceTravel Inc; he is banking on you to save his job.
Just to make things worse, Fluke’s shuttle was designed by Elbonians and not tested before being deployed due to this unforeseen emergency. You now find that the “Back”, “Left”, “Right” and “Fwd” buttons on the shuttle are unintuitive to say the least:
e.g. if Fluke’s Rover is in the slot marked as FL below (facing east), there are 4 possible slots that he can move to (shown in Blue). In short, it can not move back (towards the west) and is always facing east. He can only rescue people by moving to the slot that they are standing in.

Each survivor of the crash has a rank R (1<= R <= 5) e.g. some are Chancellors Rank5 and at the other end of the spectrum are Guards Rank1.
Determine the optimal path – that can
- save a group of people with the maximum total rank. High ranking officials are key to maintaining peace across various factions in the federation. Guards are sworn to protect them and will stay behind if required.
- If you have one optimal path, you should tell Fluke the command seq for the same. If more than one path is optimal, you should tell Fluke all the possible command seq and let him decide
- Time is of the essence – it is critical that the people be rescued as quickly as possible.

Input
- The first line contains n where n is the side of the square grid on which the rover will move. 4 <= n <= 100. Top-left co-ordinate is (0,0) and bottom right co-ordinate is (n-1, n-1)
- The next line is the number of test cases n (2 in the example below) that follow (< 5). Each test case is comprised of a number of lines.
o The first line of the test case contains the position where the space rover is beamed down/placed initially (facing east).
o The next line contains the number of survivors, k.
 This is followed by k lines, each having 3 integers relevant to each survivor. E.g. 1 3 5 indicates that there is a survivor at (1,3) and has Rank 5.

4
2
0 1
4
1 3 5
2 0 5
2 2 1
3 2 3
0 1
5
1 3 5
2 0 5
2 2 5
3 0 5
3 2 3

The test cases represent the following scenarios respectively.

Output
You should print out the results to console (via printf or equivalent)
For each test case, output the maximum cumulative rank of people you can save as the first line. That is to be followed by the command seq (1 or multiple) for the path(s) – See the example below.
8
LB
BL
10
RF

Explanation:

Rules:
• Your program must accept a string as a command line argument. It should then proceed to open the file of that name in the same/current directory, which contains one or more test cases. Output should be printed to console via printf (or equivalent).
• The program will not expect any user input. Please test your program for compile / run time errors before submitting.
• You may submit multiple submissions – strive for solutions that are elegant, memory and time efficient.
• The time limit if specified is for all the test cases to be executed; the time limit is NOT per test case

Attached Files

BIQ-004-KHAL_222.doc (50.5 KB)

Interesting C program for Accelerator

kirtics344 — Fri, 20 Nov 2009 15:33:44 GMT

You’ve been given an assorted set of gears. Each gear has a different number of teeth – the notches on a gear that interlock with notches on another gear to transmit speed. You have a couple of belts one coupled to an input and the other for the output. You are given the rpm of the input belt Si and a minimum value So (where So > Si) so that you can increase the speed via a system of gears as shown above
You need to figure out all the possible pairs of gears that can be used to achieve an output rpm >= So.
Input
The input is specified in a file containing test-cases.
• The first line contains the number of gears that are available to you, g.
• The next line contains g numbers indicating the number of teeth on each gear, separated by spaces.
• The next line contains the number of test cases – n
o This is followed by n test cases. Each test case is specified by 2 speed values on a single line. (So here the first test case specifies that you need to design a gear-system that increases Si = 50 rpm to a value above 200 rpm)
7
20 10 4 6 40 25 100
2
50 200
35 75

Output
9
15

E.g. for raising the speed from 50 to 200, any of the following 9 pairs can be used
[100, 6] [40, 6] [25, 6] [25, 4] [20, 4] [40, 4] [100, 4] [100, 20] [100, 10]

Rules :
• Your program must accept a string as a command line argument. It should then proceed to open the file of that name in the same/current directory, which contains one or more test cases. Output should be printed to console via printf (or equivalent).
• The program will not expect any user input. Please test your program for compile / run time errors before submitting.
• You may submit multiple submissions – strive for solutions that are elegant, memory and time efficient.
• The time limit if specified is for all the test cases to be executed; the time limit is NOT per test case
* We would compile your program into an executable and run it (e.g. c:\>X.exe TestCases.txt)

How to create a dynamic array in recursion?

beatenbob — Fri, 20 Nov 2009 12:55:13 GMT

Hi all. Just a simple question but I SERIOUSLY need some help from you guys for my programming assignment.

The assignment given was water jug problem.

Now my question is, does C allow for the creation of dynamic array during a recursion?
Suppose I have another function, which returns a value (well in my case the function returns a character), and I'm gonna store the character into a dynamic array(which in the current function). This means that the dynamic array is constantly "enlarged" as long as another function returns a value to the current function where the dynamic array is located. If the other function stops returning a value, the whole process stops.

Thanks in advance.

Standards & Implementations

Iam3R — Fri, 20 Nov 2009 08:56:56 GMT

Hi ,
this one is with respect to C.
(i)
when we use array an array index always starts from zero .
is it a standard one? or compilers are implemented that way?
if compilers are implented that way they must have followed some standard.
(ii)
the array name cannot be changed is it the standard or compiler dependent.

i have never heard that array index starts from 1 and base address can be changed.

Thanks,
Danian

errors in C program..plz help

sahasra — Fri, 20 Nov 2009 05:57:06 GMT

Hi,
I am new to this site.
Can you please help me with this. I have written a C program and i m getting the following errors
1) " 'puts' was not declared in scope "
the same error for 'gets' and 'itoa' command...i have included stdio.h,string.h,stdlib.h,math.h as the header files
2)" expected constructor , destructor or type conversion before '=' token " ......for the code k=1.92 ....i have declared 'k' as a float
3) expected ',' before '}' token

kindly clear my queries
Thank you,
sahasra.

A challenging problem in Recursion

Tamaki — Fri, 20 Nov 2009 04:30:08 GMT

At least for me it is:)
This is an assignment problem and I can really use some help!

INTRO TO PROBLEM:
So the problem is a basic logic problem, where I'm sure you're all familiar with...
From my assignment page, the problem

Imagine that you have 2 jugs, a small one and a large one, with integer capacities of sCap

and lCap gallons, respectively (sCap < lCap). Initially both jugs are empty. You are

allowed to completely fill each jug from a tap, or empty them on the ground. You can also

pour one jug into the other: pouring stops when either the receiving jug is full or no water is left

in the pouring jug (i.e. no water is spilled). Note that each pouring action will cause a positive

number of whole gallons to be transferred.

Given two integer values sFinal and lFinal, the problem is to find a valid sequence

of actions such that after performing the actions, the small and large jugs contain exactly

sFinal and lFinal gallons of water, respectively.

WHAT I NEED HELP ON
Basically I have a few functions that are ready to be used...
I will attach a .c file at the end of this post for the code...
I took a long time checking over this post and adding comments, any sort of help on recursion is appreciated...
I just don't understand how to start this recursion

#include 

#include 

#include 

#include 

#include 



char  *solve(const char curSequence[], int sCur, int lCur, int sCap, int lCap, int sFinal, int lFinal);

void prettyPrint(const char solution[], int sCap, int lCap);

bool actionIsPossible(char action, int sCur, int lCur, int sCap, int lCap);

void getUpdatedJugsAmounts(char action, int sCur, int lCur, int sCap, int lCap, int *sUpdated, int *lUpdated);

bool occurs(const char curSequence[], int sVal, int lVal, int sCap, int lCap);

bool applyAction(char action, const char curSequence[], int sCur, int lCur, int sCap, int lCap, char updatedSequence[], int *sUpdated, int *lUpdated);



//a testing main method that was given

int main(int argc, char *argv[])

{

  int sCap, lCap, sFinal, lFinal;

  if (argc < 5)

  {

    printf("Usage: jugs smallCapacity largeCapacity smallFinal largeFinal\n");

    return 0;

  }

  sCap = atoi(argv[1]);

  lCap = atoi(argv[2]);

  sFinal = atoi(argv[3]);

  lFinal = atoi(argv[4]);*/



  char *solution;

  solution =  solve("", 0, 0, 3, 4, 0, 2);

  printf("The solution is: %s\n", solution);

  if (strcmp(solution, "Not Found") != 0)

     prettyPrint(solution, sCap, lCap);



  free(solution);

  return 0;

}

//This is the function I'm having trouble with...

//Basically this function should follow this idea

////////////////////////////////////////////////////////////////////////

/*char *solve(curSequence, curConfig, capacities, finalConfig)

//        if the current configuration == the final configuration then

//                it means that no further action is needed so simply

//                allocate space and return a copy of curSequence as the solution

//        else

//                pick one of the 6 actions and apply it to the curConfig

//                (you may want to call applyAction)

//                if the action is applicable (i.e. it is possible and it

//                does not create a cycle) and a recursive call to

//                solve(updatedSequence, updatedConfig, capacities, finalConfig)

//                returns a solution then return this solution

//                otherwise clean up any dynamically allocated spaces and if any

//                un-tried action is left, then try it (as above)

//                if no more action is left to try then

//                allocate space and return the string "Not Found".8?*/

//////////////////////////////////////////////////////////////////////

///////////////////my crappy recursion////////////////////////////////

char *solve(const char curSequence[], int sCur, int lCur, int sCap, int lCap, int sFinal, int lFinal){

        if (sCur == sFinal && lCur == lFinal) {

                int i;

                for(i = 0; curSequence[i] != '\0'; i++);

                char *solution = (char *)malloc(i*sizeof(char *));

                strcpy(solution,curSequence);

                return solution;

        }

        else {

            char *solution = (char *)malloc(sizeof(char *));

            printf("here\n");

            char *curAct = (char *) malloc (sizeof(char *));

            char god[] = {'f', 'F', 'p', 'P', 'e', 'E'};

            int i;

            for(i = 0; i < 6; i++){

            if(applyAction(god[i], solution, sCur, lCur, sCap, lCap, curAct, &sCur, &lCur)){

                curAct = solve(solution, sCur, lCur, sCap, lCap, sFinal, lFinal);

                printf("recur\n");

            }

            else

                free(curAct);

            strcat(solution,curAct);

            return solution;

        }

               solution = (char *)malloc(sizeof(char)*(strlen("Not Found") + 1));

        strcpy(solution,"Not Found");

        return solution;

}

//A simple print method in the format  A1  so on

void prettyPrint(const char curSequence[], int sCap, int lCap){

        int i, j = strlen(curSequence)+1;

        int s = 0, l = 0;

        for(i = 0 ; i < j; i++){

                printf("<%d,%d> ", s, l);

                getUpdatedJugsAmounts(curSequence[i], s, l, sCap, lCap, &s, &l);

                printf("%c ", curSequence[i]);

        }

}

//There are certain restrictions on which action is possible at a given configuration

//returns true if possible, false otherwise

bool actionIsPossible(char action, int sCur, int lCur, int sCap, int lCap){

    bool final = false;

    if (action == 'f' && sCur < sCap){final = true;} //the small jug is not already full

    else if (action == 'F' && lCur < lCap){final = true;} //the big jug is not already full

    else if (action == 'p' && sCur > 0 && lCur < lCap){final = true;} //the small jug is not empty AND the big jug is not full

    else if (action == 'P' && lCur > 0 && sCur < sCap){final = true;} //the big jug is not empty AND the small jug is not full

    else if (action == 'e' && sCur > 0){final = true;} //the small jug is not already empty

    else if (action == 'E' && lCur > 0){final = true;} //the big jug is not already empty 

    return final;

}

//calculated the new amounts and returns them through pointers

void getUpdatedJugsAmounts(char action, int sCur, int lCur, int sCap, int lCap, int *sUpdated, int *lUpdated){

    *sUpdated = sCur; *lUpdated = lCur;

    if (action == 'f'){*sUpdated = sCap;}

    else if (action == 'F'){*lUpdated = lCap;}

    else if (action == 'p'){for (; lCur < lCap && sCur > 0; sCur--, lCur++);*sUpdated = sCur; *lUpdated = lCur;}

    else if (action == 'P'){for (; sCur < sCap && lCur > 0; lCur--, sCur++);*sUpdated = sCur; *lUpdated = lCur;}

    else if (action == 'e'){*sUpdated = 0;}

    else if (action == 'E'){*lUpdated = 0;}

}

//If the given sequence does not for a repeated config/cycle

//ie: if you start wiht <0,0> and perform PP on sCap = 3 lCap = 4, first <0,4> then <0,4>, which gives u a repeated configuration...

//returns true if there is a repeated config, false otherwise

bool occurs(const char curSequence[], int sVal, int lVal, int sCap, int lCap){

    int i, j = strlen(curSequence)+1;

    int sCur = 0, lCur = 0;

    bool final = false;

    if (sVal == 0 && lVal == 0){final = true;}

    for (i = 0; i < j ; i++){

         //printf("%d = %d %d = %d\n",sCur,sVal,lCur,lVal);

        if (actionIsPossible(curSequence[i], sCur, lCur, sCap, lCap)){

                getUpdatedJugsAmounts(curSequence[i], sCur, lCur, sCap, lCap, &sCur, &lCur);

                if (sCur == sVal && lCur == lVal){final = true;}

        }

}

    return final;

}

//apply the action, update the sequence with the new action, and pass the new values back with points and the updated sequence with the array.

//return true if the action is possible and does not cycle, false otherwise

bool applyAction(char action, const char curSequence[], int sCur, int lCur, int sCap, int lCap, char updatedSequence[], int *sUpdated, int *lUpdated){

        bool final = false;

        strcpy(updatedSequence,curSequence);

        int s = 0, l = 0;

        const char act[2] = {action};

        if (actionIsPossible(action, sCur, lCur, sCap, lCap)){

                getUpdatedJugsAmounts(action, sCur, lCur, sCap, lCap, &s, &l);

                if (!occurs(curSequence, sCur, lCur, sCap, lCap)){

                        *sUpdated = s;

                        *lUpdated = l;

                        updatedSequence = strcat(updatedSequence,act);

                        final = true;

                }

        }

        return final;

}

Thank you again for any help!

Attached Files

Waterjugs.c (6.7 KB)

round robin

lathachowdary — Fri, 20 Nov 2009 04:25:11 GMT

i want program for round robin in c

left operand of -> has incompatible type

agentmusic — Thu, 19 Nov 2009 21:40:32 GMT

Hello

Im trying to compile the following code but I get the error "left operand has incompatible type" because of the line:

test2_2_U->Out2= test2_2_U->Out3;

I have been looking through the forum but I couldnt find a hint what Im doing wrong. Any hint is appreciated.

Thanks Thomas

static BlockIO_test2_2 test2_2_B;      /* Observable signals */

static D_Work_test2_2 test2_2_DWork;   /* Observable states */

static ExternalInputs_test2_2 test2_2_U;/* External inputs */

static ExternalOutputs_test2_2 test2_2_Y;/* External outputs */



void rt_OneStep(RT_MODEL_test2_2 *test2_2_M)

{

 

 test2_2_step(&test2_2_B, &test2_2_DWork, &test2_2_U, &test2_2_Y);

 test2_2_Y->Out2=  test2_2_Y->Out3;



}

where test2_2_U is defined as:



   66   typedef struct {

   67     real_T Out1_f;                       /* '/Out1' */

   68     real_T Out2;                         /* '/Out2' */

   69     real_T Out3;                         /* '/Out3' */

   70     real_T Out4;                         /* '/Out4' */

   71   } ExternalOutputs_test2_2;

   72

Problem with permuting bits

kolosick.m188 — Thu, 19 Nov 2009 20:44:04 GMT

I am having a slight problem implementing this code. What I need to do is take a list of 16 unsigned characters and permute the bits according to IPTable. 0 in IPTable refers to bit 0, 1 refers to bit 1, etc. Here is my code which isn't working.

unsigned char IPTable[128] = {0, 32, 64, 96, 1, 33, 65, 97, 2, 34, 66, 98, 3, 35, 67, 99, 4, 36, 68, 100, 5, 37, 69, 101, 6, 38, 70, 102, 7, 39, 71, 103, 8, 40, 72, 104, 9, 41, 73, 105, 10, 42, 74, 106, 11, 43, 75, 107, 12, 44, 76, 108, 13, 45, 77, 109, 14, 46, 78, 110, 15, 47, 79, 111, 16, 48, 80, 112, 17, 49, 81, 113, 18, 50, 82, 114, 19, 51, 83, 115, 20, 52, 84, 116, 21, 53, 85, 117, 22, 54, 86, 118, 23, 55, 87, 119, 24, 56, 88, 120, 25, 57, 89, 121, 26, 58, 90, 122, 27, 59, 91, 123, 28, 60, 92, 124, 29, 61, 93, 125, 30, 62, 94, 126, 31, 63, 95, 127};



void IP(unsigned char * input, unsigned char * output)

{

        unsigned char i;

        for (i = 0; i < 128; i++)

        {

                output[i / 8] ^= (128 >> (IPTable[i] % 8)) & input[IPTable[i]];

        }

Thanks for the help. By the way this code definitely won't work if output isn't set to all zeroes, I already know that and that isn't the error.

shell programming in c

dena — Thu, 19 Nov 2009 18:09:39 GMT

hi
please can any one help me in my shell project
like this :

Develop a c program which serve as s shell interface that accepts user command and then executes each command in separate process. The shell interface provides a command prompt ( sh> ) after which next command is entered .

#define TRUE 1 



while(TRUE){ //repeat forever 

  type_prompt(); //display prompt on the screen 

  read_command (command, parameters); //read input from terminal 

  if(fork()!=0){ //fork off child process 

  waitpid(‐1, &status, 0); //wait for child to exit 

  } 

else{ 

  execve(command, parameters, 0); //execute command 

  } 

}

Write a shell that is similar to the above code snippet, but contains enough code that it actually works so you can test it. You may also add some features such as redirection of in input and output, pipes, and background jobs.
If the user entered “& “ at the end of his/her command, then the process (command) will be executed in the background and the shell WILL Not WAIT It To Terminate.
You can experience background process yourself by trying the following command on bash shell.
> kwrite
The kwrite application will be run, and the shell prompt will not prompt a user until you terminate kwrite. On the contrary, if you tried the following command, the prompt will return to the user to accept other commands while kwrite (child process) is running in the background!
please

Code Snippet Linked List

xavier666 — Thu, 19 Nov 2009 05:52:48 GMT

This is just a linked list program for those who need help understanding the fundamentals. Put comments if you find some bugs.
The program is about maintaining a student database (their roll number and their age)
I've used Turbo C++ 4.5 as the compiler

:icon_cool:

Comparing different lines in a file

flipjoebanana — Thu, 19 Nov 2009 04:31:55 GMT

Hello,
If I want to say compare a line at a given line number to another line at a different given line number how can I do this? I know I could iterate through the file and store the lines into a data structure and perform comparisons that way but the file is very large and was wondering how I could avoid that without taking up more memory? Or any other thoughts, thanks.

help with adding primes

eskaflowne — Thu, 19 Nov 2009 03:23:39 GMT

now I have never posted before so I hope this is in the right spot/format..

this problem is driving me insane. I need prove the Goldbach conjecture that is, "every even integer n > 2 is equal to the sum of 2 prime numbers." Then with a starting point and ending point prove this. (Ei: start at 2 end at 10 => 2 = 1 +1, 4 = 1 + 3....10 = 5 + 5)

The problem that I have is that I cant seem to figure out what is wrong with my code. When I run it the loop jumps over some intervals that it couldn't find a prime for and I just don't really know how to fix this as well as making the intervals go up 2 instead of 1 without a syntax error.

now this is what I have so far...

#include 

#include 

#include 





/* function to create a random number */



int randomInteger(int low, int high)

{

        static short firstRun = 1;

        int offset;

        if(firstRun)

        {

                //If this is the first call to this procedure, randomize the seed

                srand(time(NULL));

                //and set first run to 0 so we know its  been run

                firstRun = 0;

        }

        offset = low;

        low = 0;

        high -=offset;

        return ((rand()%high)+offset);

}





/* function to see if a number is prime */



int prime_check(int num)

{

        int i;

        int check = 0;



        for(i=1;i<=num;i++)

        {

                if(num % i == 0)

                {

                        check = check +1;

                }

        }



        if(check == 2)

        /* printf("number is prime\n"); */

        return 1;



        else

        /*printf("number is not prime\n");*/

        return 0;

}









int main()

{

        int a,b,i;

        int prime1, prime2;

        int start = 2;

        int end = 20;





        for(i = start; i <= end; i++)

        {

                prime1 = randomInteger(1,i);



                a = prime_check(prime1);



                if(a==1)

                {

                        prime2 = (i - prime1);



                        b = prime_check(prime2);



                        if(b==1)

                        printf("%d = %d + %d\n", i, prime1, prime2);



                        else

                        randomInteger(1,i);

                }



                else

                randomInteger(1,i);





                /*lets me see what numbers the program skipped*/



                printf("%d\n", i);





        }



        return 0;

}

when I compile and run it I get something that looks like this...

2
3
4 = 2 +2
5 = 3 +2
6
7 = 5 + 2
8 = 5 + 3
9
10 = 5 +5
11
12
13
14 = 7 +7
15
16
17
18 = 5 + 13
19 = 17 + 2
20

Hash and Rehash

MeBjess — Thu, 19 Nov 2009 01:32:49 GMT

I have been working on a basic accounting program, the accounts were supposed to be stored in a array, but I never got that part of the program working. Is there anyway I can get a sample of hash code that would help me understand what I need to do? In my case, I am trying to get the account numbers to be stored in the hash array (that's how he worded it in class). I have searched through my book for the class and I did not find anything about hashing.

Any tips, tricks, or code sample would be appreciated.

Thanks in advance!

decimal to binary, palindrome!

lisedaton — Wed, 18 Nov 2009 22:58:27 GMT

hi all!!,

can somebody help me??

I need to do a program that scan a decimal, transform it to binary and check if it is palindrome or not and print "palidrome" or "not palindrome"....

i can only use functions and cant use arrays or anything else!

can somebody help me???
these week i got really sick and i need to give that in and im blank!!... help!

thanx

read a string input

bufospro — Wed, 18 Nov 2009 20:36:21 GMT

Hi,
I want to make a program that reads a string.
But I would like to read only characters, neither numbers nor special characters(@,#$%^&*()!). Also, no spaces between characters.

#include 

#include 



char *enter_a_string(int maxcharacters)

{



        char *ptr;

        int len;



        printf("Enter string : ");

        char array[50];



        do{

                scanf("%s",array);

                  len = strlen(array);

                        

                if(len > maxcharacters)

                {

                        printf("Maximum %d  characters. Try again : ",maxcharacters);

                }



        }while(len > maxcharacters);



        ptr = array;



return ptr;

}



int main()

{

        char array[50];

        strcpy(array,get_personal_elements(15));

}

Could someone help me please?
Thanks a lot

simple string problem

Ineedhelpplz — Wed, 18 Nov 2009 17:51:07 GMT

So everything in my program works except for the main itself. The program is supposed to take in a file provided through standard input and print out the descending order of words followed by the frequency that they occur. I can do this individually line for line but am having trouble putting it together as a whole to count all the lines and not just one specific line. Here is my code:

blade71(382)% cat test.c

#include 

#include 



#define MAX_WORD_LENGTH    31

#define MAX_TEXT_LENGTH 10000

#define TRUE                1

#define FALSE               0

#define BUFSIZE 100



/* Structure defining a count of the occurrences of a given word */

struct WordCounter

{

 char *word;

 int word_count;

 struct WordCounter *pNext;  /* Pointer to the next word counter in the list */

};



      /* Function prototypes */

void addWord(char *pWord);

/* Adds a word to the list or updates exisiting word */

int is_separator(char ch);

/* Tests for a separator character */

void show(struct WordCounter *pWordcounter);

/* Outputs a word and its count of occurrences */

struct WordCounter* createWordCounter(char *word);

/* Creates a new WordCounter structure */

int getword(char *, int);

/* Self explanitory */

int getch(void);

void ungetch(int);



      /* Global variables */

struct WordCounter *pStart = NULL;

/* Pointer to first word counter in the list */

char buf[BUFSIZE];

int bufp = 0;



main()

{

 char text[MAX_TEXT_LENGTH];    /* Stores input text */

 char buffer[MAX_WORD_LENGTH];  /* Buffer to hold a word */

 size_t i = 0;                  /* Index to text */

 int len = 0 ;                  /* Word length */

 struct WordCounter *pCounter = NULL;  /* Pointer to a word counter */

 printf("Calculating frequency of word occurances:\n");

gets(text); This line only gets the first line.  To get the next I thought I could do something like footnote 1.



/* Extract the words from the text  */

 while(text[i] != '\0')

 {

  /* Skip over separators */

  while(is_separator(text[i]))

  ++i;

  /* It is either the end of the string or the start of a word    */

  /* As long as it is not the string terminator copy the character */

  len = 0;              /* Reset character count    */

  while((!is_separator(text[i])) && (text[i] != '\0'))

  buffer[len++] = text[i++];

  if(len>0)               /* Check we have some characters in the word */

    {

     buffer[len] = '\0';   /* We reached the end of a word so add terminator */

     addWord(buffer);      /* Add the word to the list */

    }

  }

                                                                                 /* List the words and their counts */

 pCounter = pStart;

 while(pCounter != NULL)

  {

   show(pCounter);

   pCounter = pCounter->pNext;

  }

 printf("\n");

 /* Free the memory that we allocated */

 pCounter = pStart;

 while(pCounter != NULL)

  {

   free(pCounter->word);        /* Free space for the word */

   pStart = pCounter;           /* Save address of current */

   pCounter = pCounter->pNext;  /* Move to next counter    */

   free(pStart);                /* Free space for current  */

  }

}



/* Returns TRUE if the argument is a separator character and FALSE otherwise */

int is_separator(char ch)

{

 /* Separators are space, comma, colon, semicolon, double quote, question mark, exclamation, and period */

 static char separators[] = { ' ' , ',',':' , '\"', '?' , '!' , '.'};

 int i = 0;

 for(i = 0 ; i
  {

   if(ch == separators[i])

   return TRUE;

  }

 return FALSE;

}

                                                                                void show(struct WordCounter *pWordcounter)

{

 /* output the word left-justified in a fixed field width followed by the count */

 printf("\n%-30s   %5d", pWordcounter->word,pWordcounter->word_count);

}



void addWord(char *word)

{

 struct WordCounter *pCounter = NULL;

 struct WordCounter *pLast = NULL;

 if(pStart == NULL)

  {

   pStart = createWordCounter(word);

   return;

  }

                                                                                 /* If the word is in the list, increment its count */

 pCounter = pStart;

 while(pCounter != NULL)

  {

   if(strcmp(word, pCounter->word) == 0)

    {

     ++pCounter->word_count;

     return;

    }

   pLast = pCounter;            /* Save address of last in case we need it */

   pCounter = pCounter->pNext;  /* Move pointer to next in the list        */

  }



 /* If we get to here it's not in the list - so add it */

   pLast->pNext = createWordCounter(word);

}



/* Create and returns a new WordCounter object for the argument */

struct WordCounter* createWordCounter(char *word)

{

  struct WordCounter *pCounter = NULL;

  pCounter = (struct WordCounter*)malloc(sizeof(struct WordCounter));

  pCounter->word = (char*)malloc(strlen(word)+1);

  strcpy(pCounter->word, word);

  pCounter->word_count = 1;

  pCounter->pNext = NULL;

  return pCounter;

}

while(scanf("%s",&text[x] != EOF))

{

gets(&text[x]);

x++;

}

However, C being the type dependent pain in the ass that it is...this doesn't work or I'm just unaware of how to cast it to work.

bios.h: No such file or directory

jmangu — Wed, 18 Nov 2009 17:27:36 GMT

Hello,

I'm trying to compile a program related with serial communication via RS232. I've found this program at microsoft page http://support.microsoft.com/?scid=k...1&x=9&y=11#top. When I try to compile this same program in Dev C++ editor the following message appears:
bios.h: No such file or directory. Please, help me about what can I do in order to advance or give me an alternative solution. Thanks in advance.

/* Compile options needed: none

 - The following program is a simple example which sends and receives

   one character to/from COM1:

*/ 



#include 

#include 



void main(void)

{

    unsigned com1_status;

    unsigned com1_send;

    unsigned com1_rec;

    unsigned com1_init;

    int result, mask;



    /* open serial port at 1200 baud, 8 data bits,

    ** No parity, 1 stop bit */ 

    com1_init = _bios_serialcom(_COM_INIT, 0,

        _COM_CHR8 | _COM_NOPARITY | _COM_STOP1 | _COM_1200);

    printf("Init status: 0x%4.4X\n", com1_init);



    /* send an '*' to com1 */ 

    com1_send = _bios_serialcom(_COM_SEND, 0, '*');

    printf("Send status: 0x%4.4X\n", com1_send);



    mask = 0x6100;

    /* value used to mask:

    *    bits 0-7 are related to modems,

    *    bits 8-15 are for port status,

    *      check to see that the following bits are set:

    *         8 (data ready)

    *        13 (Transmission-hold  register empty)

    *        14 (Transmission-shift register empty)

    */ 



    /* check the status */ 

    com1_status = _bios_serialcom(_COM_STATUS, 0, 0);

    printf("COM1 status: 0x%4.4X\n", com1_status);



    /* wait until a character is ready */ 

    do {

        /* check the status */ 

        com1_status = _bios_serialcom(_COM_STATUS, 0, 0);



        /* mask off the low order byte of com1_status */ 

        com1_status = com1_status & 0xFF00;

    } while( (mask & com1_status) == 0);



    /* get a character */ 

    com1_rec =  _bios_serialcom(_COM_RECEIVE, 0, 0);

    printf("Read status: 0x%4.4X\n", com1_rec);



    /* print the character we just received */ 

    result = com1_rec & 0x00FF;

    printf("Character: 0x%2.2X  =  %c\n", result, (char)result);

}

Dynamic include in C

ahamed101 — Wed, 18 Nov 2009 17:17:29 GMT

Hi All,
Let me explain the problem.

I have multiple include files as in class1.inc, class2.inc, class3.inc etc. Contents of an include file will be like

class1.inc

{

"john",

12,

68,



"steve",

12,

98,



"mat",

12,

95,



};

This will basically serve as a static array of structures. Here there are three field name(char*), age(int), avg(float).
In my program I want to assign the value of one of these file to a structure variable. My code goes like this

struct std_

{

        char name[50];

        int age;

        float avg;

}

std_str, *std_ptr;



int main(int argc, char **argv)

{

                

        if(!strcmp(argv[2],"class1")

        {

                static std_str obj[200] = 

                #include "class1.inc"

                

                ...

        }

        else if(!strcmp(argv[2],"class2")

        {

                ...        

        }

return 0;

}

The above code will work fine. But what I want is

int main(int argc, char **argv)

{

        char file[50];



        /* I want to dynamically generate the include file name and include it */

        strcat(file, argv[2]);

        strcat(file, ".inc")

                

        static std_str obj[200] = 

        #include file

        

return 0;

}

But unfortunately, the compilation fails, saying #include expects a file name.

Is there anyway to achieve this?

Thanks and Regards,
Ahamed.

Asynchronous Server with threads

siggivara — Wed, 18 Nov 2009 13:20:46 GMT

I'm trying to create a simple server that starts a new thread for each new client that connects. I know I can use fork(), but I've heard that threads are more efficient. Also I have some global queues, so if I used fork(), each process would get their own version of the queues. (I could fix this with shared memory).

But I'm not sure where to implement this in my code.
Heres the pseudocode of my server and main accept() loop:

Global queue1;

Global queue2;





while(1) {

    

    

    

    

}

So I need to know where/how, in my code, to implement threads, and which type of threads to use. It is supposed to run on Linux.
Also I need to know how to synchronize Global queue1 and Global queue2 so that the threads can access and write/delete from them without problems.

How to output all the letters of the alphabet randomly?

Jelmund — Wed, 18 Nov 2009 11:01:40 GMT

Hello people :)

My teacher gave me a new project to work on.
I need to write an application that output all the letters of the alphabet in a random order.
I've made some applications before but im still kinda new to this.
Could any of you give me a hint or put me in the right direction?

Kind regards,
Jelmund

PS: i already searched on the internet

Socket programming in C

george_82 — Tue, 17 Nov 2009 08:11:30 GMT

Hi all,
How to do socket programming in C.I need to control an external device through TCP/IP or UDP/IP so that when I send a query the device should be capable to respond.

Interrupts in C

Mathura — Tue, 17 Nov 2009 04:26:57 GMT

Dear colleagues I am currently working on designing a scheduler using Borland C. I am struck with the concept of interrupts. I am trying clock tick interrupt for task switching. In all materials they say you will continue to your regular job until the interrupt occurs. I don't think it suddenly occurs with out setting it in the context of the task. this is my first project in C. currently my tasks don't have separate stack of their own. all share the same stack. so i will be happy if you people tell me in what way i should update my knowledge.
in my part i will help to you people too.

find the 3rd ',' in a string line

ubi_ct83 — Tue, 17 Nov 2009 02:08:46 GMT

Hi experts,

i have this line of string: a1,b2,c3,a2,b1,c2,a3,b2,c4,

from this line,i want to load into a string array like this:
array[0]=a1,b2,c3,
array[1]=a2,b1,c2,
array[3]=a3,b2,c4,

seriously i have no idea at all.ive done sumthing but looks like rubbish.i really hope dat u experts can help me.

thanks for advance

void seeding()

{

   char seed_array[100];//line of characters in this array

   printf ("seed real=> %s\n",seed);

   char *p=NULL;



   for (int i=0;i<= 100;i++)

   {

       p=strchr(seed,',');

       if (atoi(p)==3)

       {

        strcpy (seed_array[i],p);

        *p='\n';

       }

       printf ("seed array=> %s\n",seed_array[i]);

   }



   printf("seeding test is running!!!!\n");

 }