#include <iostream>
#include <fstream>
#include <map>

using namespace std;

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

map <int, int> v;

int main()
{
    ///foloseim un map in care retinem perechi de forma (x, x).
    int tip, x, n;
    fin>>n;
    for(int i = 0; i < n; i++)
    {
        fin>>tip>>x;
        switch (tip)
        {
            case 1:         ///se adauga elem x in multime
            {
                v.insert(pair<int, int>(x, x));
                break;
            }
            case 2:         ///se sterge elem x din multime
            {
                v.erase(x);
                break;
            }
            case 3:         ///returneaza 1 daca x e in multime si 0 in caz  contrar
            {
                if(v.find(x) == v.end())
                    fout<<0<<'\n';
                else
                    fout<<1<<'\n';
                break;
            }
        }
    }
    return 0;
}