OJ Board

//why am i continuously getting RE?? :(

//my code:

#include <stdio.h>

int main()
{
int n, m;
int val, ex, i,j;
scanf("%d", &n);
while(n)
{
scanf("%d", &m);
int num1[m], num2[m];
int sum[m];
for(i=0; i<m; i++)
{
scanf("%d %d", &num1[i], &num2[i]);
}
ex=0;
i=m-1;
while(i>=0 ...