#include<bits/stdc++.h>
using namespace std;
long long calc(int st, int num){
    int ed = st + (num - 1) * (-4);
    return 1ll * (st + ed) * num / 2LL;
}
int main(){
    int T; scanf("%d", &T);
    while (T--){
        int n, m;
        scanf("%d%d", &n, &m);
        m = min(m, n/2);
        printf("%lld\n", calc(2*n-3, m));
    }
}