Help me in solving PROC18A problem

My issue

it work on example test case but when i submit the code , none of the hidden test cases work.

what I did was, i used 2 for loop to traverse the loop in the nested for look i added the k girls in the track and i put that in the max variable with an if,

explain what i did wrong if you can or give me the solution with explanation

Thanks in Advance

My code

#include <stdio.h>

int main(void) {
	// your code goes here
	int t;
	scanf("%d", &t);
	while(t--) {
	    int n, k, max = 0;
	    scanf("%d %d", &n, &k);
	    int g[n]; 
	    for(int i = 0; i < n; i++) {
	        scanf("%d ",&g[i]);
	    }
	    for(int i = 0;i < n - k; i++) {
	        int sum = 0;
	       // printf("%d", i);
	        for (int j = i; j < k+i; j++) {
	            sum += g[j];
	        }
	        if(max < sum) {
	            max = sum;
	        }
	    }
	    printf("%d\n", max);
	}
	return 0;
}


Problem Link: PROC18A Problem - CodeChef

@vikkassolo
the i loop will be from i=0 till i<=n-k