#include <iostream>
#include <fstream>
#include <set>
using namespace std;

long long n , x;
int op;

set <long long> sir;

int main()
{
	ifstream f ("hashuri.in");
	ofstream g ("hashuri.out");
	
	f >> n;
	
	for (long long i = 1 ; i <= n ; ++i)
	{
		f >> op >> x;
		
		if (op == 1)
			sir.insert(x);
		
		else if (op == 2)
			sir.erase(x);
		
		else
		{
			if (sir.find(x) == sir.end())
				g << 0 << "\n";
			else g << 1 << "\n";
		}
	}
	return 0;
}