#include <fstream>
#include <unordered_map>

using namespace std;

ifstream fin("hashuri.in");
ofstream fout("hashuri.out");

int n;
unordered_map<int, bool> hm;

int main() {
  fin >> n;
  for (int i = 1; i <= n; ++i) {
    int t, x;
    fin >> t >> x;

    if (t == 1) {
      hm[x] = true;
    } else if (t == 2) {
      hm.erase(x);
    } else {
      if (hm[x]) {
        fout << 1 << '\n';
      } else {
        fout << 0 << '\n';
      }
    }
  }

  return 0;
}