Why is nothing output from the function?

Question

C++ / C#

The task is this:
Given a two-dimensional array, display the sum of all prime numbers in the specified area
. after two cycles we go through all the indicated areas, but for now we are going to calculate the sum of prime numbers and display it immediately on the screen.
Below is an example if the array size is 3 by 5

The compiler stops here:

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>

int A[15][15];
int prime(int n){ 
  int i;
  for(i = 2; i < n; i++){
    if(n % i == 0){
      return 0;
    }
  }
  return 1;
}
void  obrabotka (int N, int M){
 	int k, z, l, f, S, i, j, num, che;	
 	k = 0;
 	z = 0;
 	S = 0;
 	che = 0;
 	num = 1;
 	for(k = 0; k < (N - 3); k++){
 		for(z = 0; z < (M - 3); z++){
 			i = k;
 			j = z;
 			while(i < (k + 3)){
 				che	= prime(A[i][j]);
 				if(che == 1){
 					S = S + A[i][j];	
        }
        i++;
        j++;
        che = 0;
      } 
      printf("|%4d |%3d |%3d |%6d |\n", num, k, z, S);
      printf("|------------------------|\n");	
      num++;
    }	
    
  }
}
void main ()
{
    int N, M, i, j, S;
    printf ("vvedite N i M\n");
    scanf ("%d %d", &N, &M);
    printf ("vvedite matrizu\n");
       for (i = 0; i < N; i++){
             for (j = 0; j < M; j++){
                scanf("%d", &A[i][j]);
            }
        }
        
  printf("-------------------------\n");
  printf("| num |  i |  j | result|\n");
  printf("-------------------------\n");
  obrabotka(N, M);
  getch();
 }

Thanks in advance

Answer 1

At least because in your example N = 3, and in obrabotka() the first cycle is declared like this: i.e. there will be no iteration of the loop under such initial conditions. PS: Didn't check everything else.