#include<iostream>
#include<stdio.h>
int main(){
    int test;
    scanf("%d", &test);
    for(;test > 0; test--){
        int n, m;
        scanf("%d%d", &n, &m);
        if(n == 1){
            printf("0\n");
            continue;
        }
        if(m > n/2) m = n/2;
        long long res = (long long)(n-1+n-(m*2))*(long long)(2*m)/(long long)2;
        printf("%lld\n", res);
    }
    return 0;
}