#include <bits/stdc++.h>
using namespace std;
#define int long long
int ans=0;

int canAchieveTarget(int n, int k, int target) {
    // To make all elements at least `target`, each element needs to be incremented to `target`
    // The total operations needed to achieve this
    int requiredOps = target * n;  // Total operations needed to set all elements to `target`

    return (target*n)*(k-(target*n));  // Check if we have enough operations
}

void solve() {
    int n, k;
    cin >> n >> k;
    ans=min(n, k-n);
    ans=max(ans, 0ll);
    if(ans==0){
        cout<<0<<endl;
        return;
    }

    // Binary search for the maximum value of `target` (Y)
    int left = 0, right = n, bestTarget = 0;

    while (left <= right) {
        int mid = (left + right) / 2;

        if (canAchieveTarget(n, k, mid)>ans) {
            bestTarget = mid;
            left = mid + 1;  // Try for a larger target
        } else {
            right = mid - 1;  // Try for a smaller target
        }
    }

    // The final result is X * Y, where X = K - (N * bestTarget)
    int X = k - (n * bestTarget);
    int Y = bestTarget;

    cout << X * Y << endl;
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int t;
    cin >> t;

    while (t--) {
        solve();
    }

    return 0;
}