#include <iostream>
#include <cstdio>
#define LL long long
using namespace std;
int  b, T;
LL n, m;
double c;
int main() {
    cin >> T;
    while(T --){
        scanf("%lld%lld", &n, &m);
        if(m <= n / 2){
            printf("%lld\n", m * (2 * n - 2 * m - 1));
        }
        else{
            printf("%lld\n", (n - 1) * n / 2);
        }
    }
    return 0;
}