#include <iostream>
#include <fstream>
#include <set>

using namespace std;

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

int main() {


    int n;
    fin >> n;

    set<int> numere;

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

        if (operatie == 1) {
            numere.insert(x);
        } else if (operatie == 2) {
            numere.erase(x);
        } else if (operatie == 3) {
            if (numere.count(x)) {
                fout << 1 << endl;
            } else {
                fout << 0 << endl;
            }
        }
    }


    return 0;
}