#include<stdio.h>

#include<iostream>
#include<fstream>
#include <algorithm>
#include <set>

using namespace std;

#define MAXN 1000000
set<int> v;

int main(){
	int N,M;

	ifstream input("hashuri.in");
	ofstream output("hashuri.out");

	input >> N;

	int tip,x;
	set<int>::iterator it;

	for(int i=0;i<N;i++){
		input >> tip >> x;

		switch(tip){
			case 1:
				v.insert(x);
				break;
			case 2:
				v.erase(x);
				break;
			case 3:
				it = v.find(x);
				if(it!=v.end())
					output << "1" << endl;
				else
					output << "0" << endl;
				break;
		}
	}

	input.close();
	output.close();

	return 0;
}