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something recursive...

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Join Date: Sep 2008

Posts: 11

Reputation: daniellamae is an unknown quantity at this point

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daniellamae daniellamae is offline

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Newbie Poster

something recursive...

Feb 18th, 2009

uhm, i really need help on recursion problems, and the first problem before my assignment is me because i really dont know how to do it, or how to construct it successfully... this is my assignment:

a program that will read 10 integers,display them as inputted and in reverse order,
display the minimum and the maximum imput using the following functions:

void readA(int A[])
-a function that reads an array of integers

int minimum(const int A[],int low, int high)
-a recursive function that returns the minimum element in the array A

int maximum(const int A[], int low, int high)
-a recursive function that returns the maximum element in the Array A.

void displayA(const int A[], int low, int high)
-a recursive function that displays the element of array A

void displayrev(const int A[],int low,int high)
-a recursive function that displays the elements of the array A in reverse order

*uhm, and this is my nonsense code that i've done, and even me didnt know what it is doing, but for me, at least i've tried..

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
#include<stdio.h>
#define inte 10 
 
void readA(int A[]){
int A[inte];
printf("\nenter an integer : ");
scanf("%d",A[inte]);
}
void displayA(const int A[],int low, int high){
if(low<=high)
{
printf("%d",A[low]);
displayA(A,low+1,high);
}
}
void displayrev(const int A[], int low, int high){
if (a>=0)
printf("\nA[displayrev(a-1)]");
}
main(){
int A[inte];
 
printf("Enter the numbers AGAIN : ");
scanf("%d",A[inte]);
 
}
#include<stdio.h>
#define inte 10 

void readA(int A[]){
int A[inte];
printf("\nenter an integer : ");
scanf("%d",A[inte]);
}
void displayA(const int A[],int low, int high){
if(low<=high)
{
printf("%d",A[low]);
displayA(A,low+1,high);
}
}
void displayrev(const int A[], int low, int high){
if (a>=0)
printf("\nA[displayrev(a-1)]");
}
main(){
int A[inte];

printf("Enter the numbers AGAIN : ");
scanf("%d",A[inte]);

}

there are many things that i didn't have there, i just dont know how, that's why i need help, please help me...super thanks guys...

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Join Date: Jun 2007

Posts: 59

Reputation: Chaster is an unknown quantity at this point

Solved Threads: 3

Chaster

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Junior Poster in Training

Re: something recursive...

Feb 18th, 2009

Well, we are not supposed to do your homework, but here is some code you can use as starting point. So, the code for the recursive input:

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
void readA(int A[]){
    if (nr>0) {
        printf("\nenter an integer : ");
        scanf("%d",&A[--nr]);
        readA(A);
    }
void readA(int A[]){
    if (nr>0) {
        printf("\nenter an integer : ");
        scanf("%d",&A[--nr]);
        readA(A);
    }

And also put this in the main function:

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
int main(){
int A[inte];
 
printf("How many numbers : ");
scanf("%d",&nr);
readA(A);
}     
}
int main(){
int A[inte];

printf("How many numbers : ");
scanf("%d",&nr);
readA(A);
}     
}

where nr is a variable of type int.

P.S. Sorry, I've just noticed that readA shouldn't even be recursive... Well I think its still a good example, and U can use it..

Last edited by Chaster; Feb 18th, 2009 at 10:38 am.

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Join Date: Jan 2009

Posts: 476

Reputation: csurfer is just really nice

Solved Threads: 76

csurfer

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Posting Pro in Training

Re: something recursive...

Feb 22nd, 2009

Yes you have really messed up the code at some places

Well I wont give you the codes but will help you out in pointing your errors and what you need to add to your codes.Here it goes:

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
void readA(int A[]){
int A[inte];
printf("\nenter an integer : ");
scanf("%d",A[inte]);
}
void readA(int A[]){
int A[inte];
printf("\nenter an integer : ");
scanf("%d",A[inte]);
}

This code reads entire array so run a for loop to take in all the inputs you are just taking one input.And ya you are passing array A[] from main and taking it here so why are you re-declaring that array within this function ??? There is no need for int A[inte] within.

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
void displayA(const int A[],int low, int high){
if(low<=high)
{
printf("%d",A[low]);
displayA(A,low+1,high);
}
}
void displayA(const int A[],int low, int high){
if(low<=high)
{
printf("%d",A[low]);
displayA(A,low+1,high);
}
}

This code is ok and will fulfill your requisite but don't use "const" at all instances because it may cause big problems if used without caution.

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
void displayrev(const int A[], int low, int high){
if (a>=0)
printf("\nA[displayrev(a-1)]");
}
void displayrev(const int A[], int low, int high){
if (a>=0)
printf("\nA[displayrev(a-1)]");
}

This code is nothing. It doesn't even print anything.Your approach to displayA is correct so use the same here in a different way as:

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
void displayrev(const int A[],int low, int high){
if(low<=high)
{
printf("%d",A[high]);
displayrev(A,low,high-1);
}
}
void displayrev(const int A[],int low, int high){
if(low<=high)
{
printf("%d",A[high]);
displayrev(A,low,high-1);
}
}

Now the main() .This is completely useless.

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
main(){
int A[inte];
 
printf("Enter the numbers AGAIN : ");
scanf("%d",A[inte]);
 
}
main(){
int A[inte];

printf("Enter the numbers AGAIN : ");
scanf("%d",A[inte]);

}

After the declaration of array A[inte]
call the read array A function written just for that purpose. Once this is done you can move on with your other parts of coding.

And ya try your might on a bit difficult things like finding min and max through recursion also.I don't see any code pertaining to it here.Try...