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

using namespace std;

int main(int argc, char const *argv[])
{
	ifstream fin("hashuri.in");
	ofstream fout("hashuri.out");

	uint N; fin >> N;

	unordered_set<uint> S(N);
	for (uint i = 0; i < N; i++)
	{
		uint op, x;
		fin >> op >> x;

		switch(op)
		{
		case 1:
			S.insert(x);
			break;
		case 2:
			S.erase(x);
			break;
		case 3:
			auto it = S.find(x);
			if (it == S.end())
				fout << 0;
			else
				fout << 1;
			fout << '\n';
			break;
		}
	}

	return 0;
}