#include <cstdio>
#include <iostream>
#include <cstring>
#include <queue>
#include <cmath>
#include <set>
#include <algorithm>
#include <map>
#include <vector>
#define mod 1000000007
using namespace std;
typedef long long ll;

const int N = 106;
const double inf = 0x3f3f3f3f;
const double eps = 1e-6;


int main()
{
    int t, n, m;
    scanf("%d", &t);
    while(t--){
        scanf("%d%d", &n, &m);
        if(m >= n/2){
            ll ans = (ll)n*(n-1)/2;
            printf("%lld\n", ans);
        }
        else{
            ll ans = (ll)m*(n-1)+(ll)m*(n-2*m);
            printf("%lld\n", ans);
        }
    }
    return 0;
}