#include <stdio.h>
#include <map>
#include <fstream>
 
using namespace std;
 
int N, NR;
map <int, int> M;
 
int main()
{
	ifstream input("hashuri.in");
	ofstream output("hashuri.out");
	int i, tip, x;
 
	input >> N;
 
	for (i = 1; i <= N; i++) 
	{
		input >> 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;
}