#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;
using mint = modint998244353;

int main() {
  int Q; cin >> Q;
  set<int> st;
  while (Q--) {
    int t; cin >> t;
    if (t == 1) {
      int x; cin >> x;
      st.insert(x);
    } else if (t == 2) {
      int x; cin >> x;
      st.erase(x);
    } else {
      uint ans = 0xFFFFFFFF;
      for (auto x: st) {
        ans &= x;
      }
      cout << (ans == 0xFFFFFFFF ? (int)-1: (int)ans) << endl;
    }
  }
}