#include <bits/stdc++.h>
using namespace std;
int main()
{
    cin.tie(nullptr);
    cout.tie(nullptr);
    ios_base::sync_with_stdio(0);
    int tt;
    cin >> tt;
    while(tt--)
    {
        int n,k,mx=0,g=0;
        cin >> n>>k;
        if(k<n)
            cout << 0 << endl;
        else if(1+n==k)
        {
            cout << ((n*(n+1))/2)/k<<endl;
        }
        else
        {
            n++;
            if(1+n==k)
                cout << ((n*(n+1))/2)/k<<endl;
            else
                cout << 0 << endl;
        }

    }
    return 0;
}