#include <iostream>
#include <map>

using namespace std;

int N, NR;
map <int, int> M;

int main()
{
	ifstream f("hashuri.in");
	ofstreeam g("hashuri.out");

	int i, tip, x;
    f>>N;
	for (i = 1; i <= N; i++) 
	{
		f>>tip>>x;
		if (tip == 1 && M.find(x)==M.end()) M[x] = ++NR;
		if (tip == 2) M.erase(x);
		if (tip == 3) g<<M.find(x) != M.end())<<"\n";
	}

	return 0;
}