#include <fstream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <unordered_map>
#include <cstring>
#include <climits>

#define NMAX 1000003
using namespace std;

int n;

ifstream fin("hashuri.in");
ofstream fout("hashuri.out");

unordered_map<long long int, int> v;

int main()
{
	fin >> n;
	for (int i = 1; i <= n; i++)
	{
		int op;
		long long int val;
		fin >>op>> val;
		if (op == 1)
		{
			auto itr = v.find(val);
			if (itr != v.end())
			{
				//itr->second = 2;
			}
			else {
				v.insert({ val,1 });
			}
		}
		else if (op == 2)
		{
			auto itr = v.find(val);
			if (itr != v.end())
			{
				v.erase(itr);
			}
		}
		else {
			bool ok = v.find(val) != v.end();
			fout << ok<<"\n";
		}
		
	}
	
	return 0;
}