#include <iostream>
#include <fstream>
#include <map>

using namespace std;

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

int n, nr, type, x;
map<int, int> m;

int main()
{
	f >> n;
	nr = 0;
	for(int i = 0; i < n; ++i)
	{
		f >> type >> x;
		if(type == 1 && m.find(x) == m.end())
			m[x] = nr++;
		if(type == 2)
			m.erase(x);
		if(type == 3)
			g << (m.find(x) != m.end()) << "\n";
	}
}