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

using namespace std;

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

long x, op, N ,i;

unordered_set <long long> multime;

int main()
{
	f >> N;

	for (i = 0; i < N; i++)
	{
		f >> op >> x;
		if (op == 1)
			multime.insert(x);
		if (op == 2)
			multime.erase(x);
		if (op == 3)
			g << (multime.find(x) != multime.end()) << endl;
	}

}