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

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

int N;

int main() {

    f >> N;
    unordered_set<int> numere;

    for (int i = 0; i < N; ++i) {
        int op, x;
        f >> op >> x;
        if (op == 1) {
            numere.insert(x);
        } else if (op == 2) {
            numere.erase(x);
        } else if (op == 3) {
            int rezultat = (numere.find(x) != numere.end()) ? 1 : 0;
            g << rezultat << '\n';
        }
    }

    return 0;
}