#include<fstream>
#include<unordered_set>

using namespace std;

inline void CitireMultimeAfisareRezultat()
{
	unordered_set<int>multime;
	int x, y, z;
	ifstream fin("hashuri.in");
	ofstream fout("hashuri.out");
	fin >> x;
	while(x--)
	{
		fin >> y >> z;
		if (y == 1)
			multime.insert(z);
		if (y == 2)
			multime.erase(z);
		if (y == 3 && multime.find(z) != multime.end())
			fout << 1<<endl;
		if (y == 3 && multime.find(z) == multime.end())
			fout << 0<<endl;
	}

	fin.close();
	fout.close();

}

int main()
{
	CitireMultimeAfisareRezultat();
}