//
//  main.cpp
//  hashuri
//
//  Created by Vlad Calomfirescu on 29.06.2021.
//

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

using namespace std;



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

    fin.sync_with_stdio(false);  //aparent functioneaza la optimizare,                                  fara 70p
    fin.tie(NULL);
    
    unordered_set<int> hashh;

    int n,op,x;
    fin>>n;
    for (int i=0; i<n; i++)
    {


        fin>>op;
        switch(op){
            case 1:
                fin>>x;
                hashh.insert(x);
                continue;
            case 2:
                fin>>x;
                hashh.erase(x);
                continue;
            case 3:
                fin>>x;
                if(hashh.find(x) != hashh.end())
                    fout<<1<<endl;
                else
                    fout<<0<<endl;
        }
    }

    return 0;
}