#include <fstream>
#include <vector>
using namespace std;

int n;
vector <int> mul;
vector <int>::iterator it;

vector<int>::iterator cautare(int x){
	for(it = mul.begin(); it != mul.end(); it++)
		if(*it == x)
			return it;
	return mul.end();
}

void inserare(int x){
	if(cautare(x) == mul.end())
		mul.push_back(x);
}

void stergere(int x){
	it = cautare(x);
	if (it != mul.end())
		mul.erase(it);
}

int main(){
	int operatie, x;
	ifstream f("hashuri.in");
	ofstream g("hashuri.out");
	f >> n;
	for(int i = 1; i <= n; i++){
		f >> operatie >> x;
		if(operatie == 1){
			inserare(x);
			continue;
		}
		if(operatie == 2){
			stergere(x);
			continue;
		}
		g << (cautare(x) != mul.end());
	}
	f.close();
	g.close();
	return 0;
}