This post provides implementation for zero sum sub array problem.

zero_sum.c

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

void zero_subarray(int a[], int n){

  int i, j;
  int T[n];
  T[0] = a[0];
  for(i= 1; i<n; i++){
     T[i] = T[i-1] +a[i];
     if(T[i] == 0){
        printf("\n Sub array from %d to %d adds upto zero" , 0,i);
     }
     for(j=0; j<i; j++){
       if(T[i] == T[j]){
        printf("\n Sub array from %d to %d adds upto zero" , j+1,i);
       }
     }
  }
}
int main(){
   int a[] = {4,  6,  3, -9, -5, 1, 3, 0, 2};
   int n = sizeof(a)/sizeof(a[0]);
   zero_subarray(a,n);
   return 0;
}