Program in c with functions without pointers doesn't work [closed] - c

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I have written a code and it doesn't run. However, there are no mistakes in compiler. I am stuck, could you give me a hint please where am I wrong?
I am 95% sure it is about checktable function.
P.S. I know how to do it with pointers, but I try to understand how to make it without them.
Thank you!
#include <stdio.h>
#include "genlib.h"
void fillarray (int a[50])
{
int i;
for(i=0;i<50;i++)
a[i]=rand()%10;
}
void printarray (int a[50])
{
int i;
for(i=0;i<50;i++)
printf(" %d ", a[i]);
}
int number()
{
int num;
printf("Give the number!");
num=GetInteger();
return num;
}
void checktable (int a[50], int b[50], int ar,int count)
{
int i;
count=0;
for(i=0;i<50;i++)
if (a[i]==ar)
{
b[count]=i;
count++;
}
}
main()
{
int i,a[50], b[50], N,count;
fillarray(a);
printarray(a);
N=number();
checktable(a,b,N,count);
printf("the number is used %d times", count);
printf("in places:");
for(i=0;i<count;i++)
printf("%d ",b[i]);
getch();
}

Answer 1

Approach 1: The "pointer" way:
In your code, change
void checktable (int a[50], int b[50], int ar,int count)
to
void checktable (int a[50], int b[50], int ar,int *count)
and call it as checktable(a,b,N,&count);
Approach 2: The "return" way:
Otherwise, the count which is updated in checktable() won't be reflected in main().
However, Alternatively (without using pointers), IMO, its always easier to simply return the number of occurrences via return statement. In that case , code will look like
int checktable (int a[50], int b[50], int ar)
{
int i;
int count=0;
for(i=0;i<50;i++)
if (a[i]==ar)
{
b[count]=i;
count++;
}
return count;
}
and the calling will be
count = checktable(a,b,N);
Note: Its always a good practice to initialize your variables.

Answer 2

If you don't want to use pointers,then you can return count and assign it to the count variable in main. I've improved your code here with all of it explained in the comments inside the code:
#include <stdio.h>
#include <stdlib.h> //Don't forget this header for srand and rand
#include <time.h> //For the time in srand
#include <conio.h> //For using getch()
#include "genlib.h"
void fillarray (int a[]) //leave the brackets empty
{
int i;
for(i=0;i<50;i++)
a[i]=rand()%10;
}
void printarray (int a[]) //here too
{
int i;
for(i=0;i<50;i++)
printf(" %d ", a[i]);
}
int number()
{
int num;
printf("\n\nGive the number!");
num=GetInteger();
return num;
}
int checktable (int a[], int b[], int ar) //Use int to return an int
//No need for count parameter
{
int i,count;
count=0;
for(i=0;i<50;i++)
if (a[i]==ar)
{
b[count]=i;
count++;
}
return count; //returning count
}
int main() //Use int main
{
int i,a[50], b[50], N,count;
srand(time(NULL)); //For rand to generate random numbers
fillarray(a);
printarray(a);
N=number();
count=checktable(a,b,N); //set count to the return value of checktable
//Also,no need to pass count as a parameter
printf("The number is used %d times", count);
printf(" in places:");
for(i=0;i<count;i++)
printf("%d ",b[i]+1); //Don't forget +1 otherwise output might come as place 0
getch();
return 0; //main returns int
}