//Include
#include <fstream>
#include <set>
using namespace std;

//Variabile
ifstream in("hashuri.in");
ofstream out("hashuri.out");

int n;
int tipOperatie, x;

set<int> s;
set<int>::iterator poz;

//Main
int main()
{
	in >> n;
	for(int i=1 ; i<=n ; ++i)
	{
		in >> tipOperatie >> x;
		switch(tipOperatie)
		{
			case 1:
			{
				s.insert(x);
				break;
			}
			case 2:
			{
				poz = s.find(x);
				if(poz != s.end())
					s.erase(poz);
				break;
			}
			default:
				if(s.find(x) == s.end())
					out << "0\n";
				else
					out << "1\n";
		}
		
	}
	
	in.close();
	out.close();
	return 0;
}