#include <iostream>
#include <fstream>
#include <algorithm>
#include <set>

using namespace std;

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

set <int> s;

bool contine(int x) {
	return s.find(x) != s.end();
}

void adauga(int x) {
	if (!contine(x)) s.insert(x);
}

void sterge(int x) {
	if (contine(x)) s.erase(s.find(x));
}

int main() {
	int n, k, x, op;
	f >> n;
	k = 0;

	while (n--) {
		f >> op >> x;
		if (op == 1) {
			adauga(x);
			continue;
		}
		if (op == 2) {
			sterge(x);
			continue;
		}
		g << contine(x) << '\n';
	}

	return 0;
}