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

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

    int N;
    fin >> N;

    unordered_set<long long> multime;

    for (int i = 0; i < N; i++) {
        int op;
        long long x;
        fin >> op >> x;

        if (op == 1) {
            multime.insert(x);
        } else if (op == 2) {
            multime.erase(x);
        } else if (op == 3) {
            if (multime.find(x) != multime.end()) {
                fout << 1 << '\n';
            } else {
                fout << 0 << '\n';
            }
        }
    }

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

    return 0;
}