#include <iostream>
#include <unordered_set>
#include <fstream>
using namespace std;

int main() {
    ifstream f("hashuri.in");
    ofstream g("hashuri.out");
    int N;
    f >> N;
    unordered_set<int> s;
    for (int i = 0; i < N; i++) {
        int op, x;
        f >> op >> x;
        if (op == 1) {
            s.insert(x);
        }
        else if (op == 2) {
            s.erase(x);
        }
        else if (op == 3) {
            g << (s.count(x) ? 1 : 0) << endl;
        }
    }
    f.close();
    g.close();
    return 0;
}