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

#define FAST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
using ll = long long;

int main() {
  FAST;
  
  int tc = 1, ti;
  cin >> tc;

  for (ti = 1; ti <= tc; ++ti) {
    ll n, k, i, t, l, r, mid1, mid2, ans1, ans2, ans;
    cin >> n >> k;

    l = 0; r = (1 << 30);
    t = 60; while (t--) {
      mid1 = l + (r-l)/3;
      mid2 = r - (r-l)/3;
      ans1 = mid1 * (k - mid1*n);
      ans2 = mid2 * (k - mid2*n);
      if (ans1 > ans2) {
        r = mid2;
      } else {
        l = mid1;
      }
    }

    ans = 0;
    for (i = l; i <= r; ++i) {
      ans = max(ans, i * (k - i*n));
    }

    cout << ans << "\n";
  }

  return 0;
}