#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);
		}
		else if (op == 2)
		{
				multime.erase(x);
		}
		else
		{
			if (multime.find(x) != multime.end())
			{
				g << 1 << endl;
			}
			else
				g << 0 << endl;

		}
	}

}