#include <stdio.h>

#include <map>



using namespace std;



int N, NR;

map <int, int> M;



int main()

{

	freopen("hashuri.in", "r", stdin);

	freopen("hashuri.out", "w", stdout);



	int i, tip, x;



	scanf("%d ", &N);



	for (i = 1; i <= N; i++)

	{

		scanf("%d %d ", &tip, &x);



		if (tip == 1 && M.find(x)==M.end()) M[x] = ++NR;

		if (tip == 2) M.erase(x);

		if (tip == 3) printf("%d\n", M.find(x) != M.end());

	}



	return 0;

}