#include <bits/stdc++.h>

using namespace std;

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

int N;
unordered_set <int> hashed;

int main() {
    fin >> N;
    while (N--) {
        int type, number;
        fin >> type >> number;
        if (type == 1) hashed.insert(number);
        if (type == 2) hashed.erase(number);
        if (type == 3) fout << (hashed.count(number)) << '\n';
    }

    fin.close();
    fout.close();

    return 0;
}