#include<iostream> 
using namespace std;
#include<stdio.h>
int main()
{
    int T;
    cin>>T;;
    while(T--)
    {
        int n,m;
        scanf("%d %d",&n,&m);
        if(m>n/2) m=n/2;
        printf("%lld\n",(long long)(m)*(n-1+n-2*m));
    }
}