#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, y, req, ans;
    cin >> n >> k;

    ans = 0;
    for (y = (1 << 30); y > 0; y >>= 1) {
      req = y*n;
      if (req > k) continue;
      ans = max(ans, y * (k-req));
    }

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

  return 0;
}