#include<cstdio>
#include<algorithm>
#include<cstring>
const int maxn = 1000006;
const int mod = 10007;
using namespace std;
int main()
{
    int t;
    long long n,m;
    scanf("%d",&t);
    while(t--){
        scanf("%lld%lld",&n,&m);
        if(m>=n/2)
            printf("%lld\n",n*(n-1)/2);
        else
            printf("%lld\n",(n*2-m*2-1)*m);
    }
    return 0;
}