#pragma GCC optimize("-Ofast","-funroll-all-loops")
#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=110;
int n,m;
void solve(){
    scanf("%lld %lld",&n,&m);
    int x=n/2;
    if(x<=m)    m=x;
    printf("%lld\n",m*2*n+m-m*(2*m+2));
}
signed main(){
    int T; cin>>T; while(T--) solve();
    return 0;
}