Maximum index

#include<cstdio>
using namespace std;
int main(){
    int t;
    scanf("%d", &t);
    while(t--){
        int n; scanf("%d", &n);
        int a[n++], i;
        for(i = 1; i < n; i++){
            scanf("%d", &a[i]);
        }
        int difference = 0, j, temp;
        for(i = 1; i < n; i++){
            for(j = n-1; j > i; j--){
                if(a[i] <= a[j]){
                    temp = j - i;
                    difference = max(difference, temp);
                    break;
                }
            }
        }
        printf("%d \n", difference);
    }
}