// @sagorahmedmunna

#include <bits/stdc++.h>
using namespace std;

long long n, k;

long long f(long long mid) {
  return (mid / n) * (k - mid);
}

void test() {
  cin >> n >> k;
  long long lo = 0, hi = k;
  while (lo < hi) {
    long long mid = (lo + hi) / 2;
    if (f(mid) <= f(mid + 1)) lo = mid + 1;
    else hi = mid;
  }
  cout << f(hi) << '\n';
}

int main() {
  ios_base::sync_with_stdio(0), cin.tie(0);
  int t = 1;
  cin >> t;
  for (int i = 1; i <= t; i++) {
    test();
  }
  return 0;
}