#include <iostream>
#include <fstream>
#include <unordered_set>

using namespace std;
ifstream in("hashuri.in");
ofstream out("hashuri.out");

unordered_set<int> s;

int main(){
  int k;
  in >> k;
  for(int i = 0; i<k; i++){
    int x, y;
    in >> x >> y;
    if(x == 1){
      s.insert(y);
    }
    else if(x == 2){
      if(s.find(y) != s.end()) s.erase(y);
    }
    else{
      if(s.find(y) != s.end()) out << 1 << "\n";
      else out << 0 << "\n";
    }
  }
}