hey guys, I have the assignment to build a program to decode a cryptogram puzzle using provided word tables. for each table the program should print the decoded text generated by that table and the number of actual english words in the decoded text. the encoded text is in the file crypt.txt and its less than 80 characters. the codetables are in codetables.txt and each line contains a tablein the form of an ASCII string and the program should process however many tables there are. the file dict.txt contains the dictionary which the program should use to determine word validity.

I had the program set up to save each table then test all of them at once but decided to change it to read in a table then test it immediatly and output then move onto the next table. but on restructuring it I keep getting logic errors.

please take a look at my code and see what you think, also let me know if you have tips on how I could structure this better.
thanks, i'd appreciate all the help i can get

#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>
using namespace std;

//**********************************
//*********Function Prototypes******
//**********************************
void buildAlpha (string&);
void getCrypt   (string&, string&);
void getTable   (string&, string&);
void testTable  (string&, string&, string);
int findPositionOf (char, string);
//**********************************
//********Main Function*************
//**********************************

int main(){
                                        // my arrays
string crypt;
string alpha;
//string answer;
string table, decrypt;
buildAlpha (alpha);
getCrypt   (crypt, decrypt);
getTable (table, decrypt);

   cout << "Cipher" << endl;
for(int i=0; i<80; i++)
  { cout << crypt [i]; }
   cout << " " << endl;
   cout << "Alphabet" << endl;

 for(int i=0; i<26; i++)
  { cout << alpha [i]; }
    cout << " " << endl;

 return 0;
}

//**********************************
//********Function Definitions******
//**********************************

void buildAlpha (string & alpha)
{
for(int i=0; i<26; i++)
    { alpha [i] = 'a'+i; }
}

void getCrypt (string & crypt, string & decrypt)
{
ifstream numdata;
    numdata.open("crypt.txt");
    if ( !numdata )                               // Check to make sure file was opened
    {
        cout << "Error opening file" << endl;
    }
        else
        {
        int i = 0;
   {
   getline(numdata, crypt);
   i++;
   }
for(int i=0; i<80; i++)
   { decrypt[i] = crypt [i]; }
   numdata.close();
}
}

void getTable (string & table, string & decrypt)
{
ifstream numdata;
    numdata.open("codetable.txt");
    if ( !numdata )                               // Check to make sure file was opened
    {
        cout << "Error opening file" << endl;
    }
        else
        {
        while (!numdata.eof())

           getline(numdata, table);                     //get table 1
   cout << "Table 1" << endl;
 for(int i=0; i<26; i++)
  { cout << table [i]; }
    cout << " " << endl;

           testTable (table, decrypt, crypt);           //test table 1
   cout << "Table 1 tested" << endl;
 for(int i=0; i<26; i++)
  { cout << decrypt [i]; }
    cout << " " << endl;

           getline(numdata, table);                     //get table 2
   cout << "Table 2" << endl;
 for(int i=0; i<26; i++)
  { cout << table [i]; }
    cout << " " << endl;

           testTable (table, decrypt, crypt);           //table 2 tested
   cout << "Table 2 tested" << endl;
 for(int i=0; i<26; i++)
  { cout << decrypt [i]; }
    cout << " " << endl;


           getline(numdata, table);
   cout << "Table 3" << endl;                           //get table 3
 for(int i=0; i<26; i++)
  { cout << table [i]; }
    cout << " " << endl;


           testTable (table, decrypt, crypt);           //table 3 tested against cipher
   cout << "Table 3 tested" << endl;
 for(int i=0; i<26; i++)
  { cout << decrypt [i]; }
    cout << " " << endl;

           getline(numdata, table);                     //get table 4
   cout << "Table 4" << endl;
 for(int i=0; i<26; i++)
  { cout << table [i]; }
    cout << " " << endl;

           testTable (table, decrypt, crypt);                   //table 4 tested against cipher
   cout << "Table 4 tested" << endl;
 for(int i=0; i<26; i++)
  { cout << decrypt [i]; }
    cout << " " << endl;

           getline(numdata, table);                     //get table 5
 cout << "Table 5" << endl;
 for(int i=0; i<26; i++)
  { cout << table [i]; }
    cout << " " << endl;

           testTable (table, decrypt, crypt);           //test table 5
   cout << "Table 5 tested" << endl;
 for(int i=0; i<26; i++)
  { cout << decrypt [i]; }
    cout << " " << endl;

        }

   numdata.close();
}

void testTable (string & table, string & decrypt, string crypt)
{
   int  letPos;

   for (int i=0; i<=80; i++)
   {
   char letterToLookup = crypt[i];
   letPos = findPositionOf ( letterToLookup, table );
   decrypt[ i ] = table[ letPos ];
   }
}
int findPositionOf (char letterToLookup, string table)
{
   for (int i=0; i<=26; i++)
   {
       if (letterToLookup == table[i])
          return i;
   }
}
}

this is the output that i get on compiling

sh-3.00$ g++ prog1.cpp
prog1.cpp: In function 'void getTable(std::string&, std::string&)':
prog1.cpp:91: error: conversion from 'char* (*)(const char*, const char*)' to non-scalar type 'std::string' requested
prog1.cpp:103: error: conversion from 'char* (*)(const char*, const char*)' to non-scalar type 'std::string' requested
prog1.cpp:117: error: conversion from 'char* (*)(const char*, const char*)' to non-scalar type 'std::string' requested
prog1.cpp:129: error: conversion from 'char* (*)(const char*, const char*)' to non-scalar type 'std::string' requested
prog1.cpp:141: error: conversion from 'char* (*)(const char*, const char*)' to non-scalar type 'std::string' requested
prog1.cpp: At global scope:
prog1.cpp:171: error: expected declaration before '}' token
prog1.cpp: In function 'int findPositionOf(char, std::string)':
prog1.cpp:170: warning: control reaches end of non-void function

You have brackets problems which will be impossible to solve until you format your code with consistent indentation. NetBeans and Visual Studio will do that for you. Then start counting brackets and make sure you don't have more ending brackets than starting brackets, or vice versa.

thanks guys, I made some changes, got rid of decrypt and now just call get crypt in a loop to reset it, and a few other things. The codetables come in and output correctly but there seems to be a problem with the letter switch in test table and find position. because all the decrypted code comes out the same. Once again I'd appreciate some tips. thanks any tips help a bunch.heres the new improved code

#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>
using namespace std;

//**********************************
//*********Function Prototypes******
//**********************************
void getCrypt   (string&);
void getTable   (string&, string&);
void testTable  (string&, string&);
int findPositionOf (char, string);
//**********************************
//********Main Function*************
//**********************************

int main(){
                                        // my arrays
string crypt;
string table;
getCrypt (crypt);

   cout << "Cipher" << endl;
for(int i=0; i<80; i++)
  { cout << crypt [i]; }
   cout << " " << endl;

getTable (table, crypt);

 return 0;
}

//**********************************
//********Function Definitions******
//**********************************

void getCrypt (string & crypt)
{
ifstream numdata;
    numdata.open("crypt.txt");
    if ( !numdata )                               // Check to make sure file was opened
    {
        cout << "Error opening file" << endl;
    }
        else
        {
   getline(numdata, crypt);
   numdata.close();
        }
}

void getTable (string & table, string & crypt)
{
int count = 1;
ifstream numdata;
    numdata.open("codetable.txt");
    if ( !numdata )                               // Check to make sure file was opened
    {
        cout << "Error opening file" << endl;
    }
        else
        {
                while (!numdata.eof())
                {
           getline(numdata, table);                     //get table 1
   cout << "Table " << count << endl;
 for(int i=0; i<26; i++)
  { cout << table [i]; }
    cout << " " << endl;

           testTable (table, crypt);                    //test table 1
   cout << "Table "<<count<<" tested" << endl;
 for(int i=0; i<26; i++)
  { cout << crypt [i]; }
    cout << " " << endl;

    getCrypt (crypt);
    count++;
                }
        }

   numdata.close();
}

void testTable (string & table, string & crypt)
{
   int  letPos;

   for (int i=0; i<=80; i++)
   {
   char letterToLookup = crypt[i];
   letPos = findPositionOf ( letterToLookup, table );
   crypt[ i ] = table[ letPos ];
   }
}

int findPositionOf (char letterToLookup, string table)
{
   for (int i=0; i<=26; i++)
   {
       if (letterToLookup == table[i])
          return i;
   }
}

I still get this error but it does compile

prog1.cpp: In function 'int findPositionOf(char, std::string)':
prog1.cpp:105: warning: control reaches end of non-void function
sh-3.00$ a.out

Heres my output, see the decrypted sections are the same so the problem must be in findposition I just don't see it.

Cipher
vshx su wgcy wx mcix sy, cvwclu gcu rxxe, cvwclu wsvv rx.;`
Table 1
bcdefghijklmnopqrstuvwxyza
Table 1 tested
vshxsuwgcywxmcixsyc
Table 2
bcsdfgleuvqwxzijkmhnptayor
Table 2 tested
vshxsuwgcywxmcixsyc
Table 3
lgtakcdevpjusfybxmhzrwoniq
Table 3 tested
vshxsuwgcywxmcixsyc
Table 4
cfelsvptmxzkdbyghinjauroqw
Table 4 tested
vshxsuwgcywxmcixsyc
Table 5
cirsdgavuwhjtxmynzopflbekq
Table 5 tested
vshxsuwgcywxmcixsyc
Table 6
irsdgavuwhjtxmynzopflbekq
Table 6 tested
skivideridirqiir

Comments
Yet another cross poster wasting people's time.

mmm, see this part at line 92

char letterToLookup = crypt[i];
   letPos = findPositionOf ( letterToLookup, table );
   crypt[ i ] = table[ letPos ];

shouldn't you use crypt[ i ] = alpha[ letPos ]; ??

This is what I think you trying to do
crypted[0]= !
So you look it up in the table using findPos and return an index
lets say:
table = $%! // so " ! " is the 3rd letter in an ALPHABET
so doing crypt = table[letPos]; leaves crypt UNCHANGED

Instead

crypt[ i ] = alpha[ letPos ];

would change crypt[0] to the letter in the final alphabet
that is

alpha = abc
table = $%!

so '!' will correspond to letter c in the final alphabet

I actually edited your code an it ended like this its still a work in progress but I didnt want it to be irrecognizable to you


#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>

using namespace std;
/*
decode a cryptogram puzzle using provided word tables. 

for each table the program should print the decoded text generated by that table and the number of actual english words in the decoded text. 

the encoded text is in the file crypt.txt and its less than 80 characters. 

the codetables are in codetables.txt and each line contains a table in the form of an ASCII string and the program should process however many tables there are. 
 */
 
//**********************************
//*********Function Prototypes******
//**********************************


void getCrypted (string & crypted );
void getTable   ( string );

void testTable  ( string, string, int);
int findPositionOf (char, string);

//**********************************
//********Main Function*************
//**********************************

 string alpha = "abcdefghijklmnopqrstuvwxyz"; 

int main(){
                        
string table, decrypt, crypt;

getCrypted(crypt);
decrypt = crypt ;

//from here on just work with decrypt
 
cout << crypt<< "\n"; 

getTable (decrypt); //open tables and test 'em needs reading improvement 

cout << "\n"; 
system("pause");
 
}
 
 
void getCrypted (string & crypt )
{
ifstream numdata;
    numdata.open("crypt.txt");
    if ( !numdata )                      // Check to make sure file was opened
        cout << "Error opening file" << endl;
        
    else
     {
        
       getline(numdata, crypt);
      
       numdata.close();
       
    }
    
}
 
void getTable ( string decrypt)
{
    ifstream numdata;
    numdata.open("codetable.txt");
    if ( !numdata )                     // Check to make sure file was opened
        cout << "Error opening file" << endl;
    else
    {
        int c = 0;
          while (!numdata.eof()) //original 
         {
             string table;
             getline(numdata, table);                     //get table 1
             cout << "\nTable#" << c << ":\n" << table << "\n";
            
             testTable (table, decrypt, c);//this is the core of all the app         
  
   
                        
             c++;
     
        }
      

   numdata.close();
} 

}
 //here is the use of decrypt this cpy could be done in here
 
void testTable (string table, string decrypt, int wichTable)
{
   int  letterPos;
 
   for (int i=0; i< decrypt.size(); i++)
   {

     char letterToLookup = decrypt[i];
     letterPos = findPositionOf ( letterToLookup, table ); //this gets table to send it again? -what a waste we can accomodate this to be calc at use time
     decrypt[ i ] = alpha[ letterPos ]; //changed from table[i]
     
   }
cout << "\nTable#" << wichTable  << "tested\n";
     cout << decrypt ;
}

int findPositionOf (char letterToLookup, string table)
{
   for (int i=0; i < table.size(); i++)
   {
       if (letterToLookup == table[i])
          return i;
//note that if the crypted symbol is not in the table what the func  returns 
// is undefined, making your program crash because of invalid memory access

   }
}

I tested with these files

// crypt.txt
!@#$%^&*()

and

//codetable.txt

!@#$%^&*()_+|}{00000000000
00000000000!@#$%^&*()_+|}{

the Output was

!@#$%^&*()_+|}{

Table#0:
!@#$%^&*()_+|}{00000000000

Table#0tested
abcdefghijklmno
Table#1:
00000000000!@#$%^&*()_+|}{

Table#1tested
lmnopqrstuvwxyz

Press any key . .

as a final word you should really put effort in your code design
the first time you post it, it was very hard to see what was happening try not to be resigned with code that compiles you look foward to nice code too

Edited 7 Years Ago by namehere05: I got the tags wrong

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