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

using namespace std;

int main() {
	ifstream iff("hashuri.in");
	ofstream off("hashuri.out");
	int N;
	unordered_set<int> s;

	iff >> N;

	while (N--) {
		int op, n;
		iff >> op >> n;

		switch (op) {
			case 1:
				s.insert(n);
	
				break;
			case 2:
				s.erase(n);
				break;
			case 3:
				if (s.find(n) != s.end()) {
					off << "1" << endl;
				} else {
					off << "0" << endl;
				}
				break;
			default:
				break;
		}
	}
}