/// hashuri map
#include <iostream>
#include <fstream>
#include <algorithm>
#include <map>
#include <utility>
#define NMax 1000001
///#define f cin
///#define g cout
using namespace std;

ifstream f("hashuri.in");
ofstream g("hashuri.out");

int n, ans, x, cod;
map <int, int> M; /// map<key, element>

int main()
{
    f >> n;
    for(int i = 1; i <= n; i++)
    {
        f >> cod >> x;
        if (cod == 1 && M.find(x)==M.end()) M[x] = ++ans; /// verific daca codul e 1 si daca x mai exista in mapa.. il adaug pe x
        else if (cod == 2) M.erase(x);
        else if (cod == 3) printf("%d\n", M.find(x) != M.end());
    }
    return 0;
}