#include <fstream>
#include <unordered_set>
using namespace std;
using namespace __gnu_cxx;

int n,type,value,i;
int main()
{
    ifstream f("hashuri.in");
	ofstream g("hashuri.out");
	unordered_set<int, hash<int> > M;
	f >> n;
	for (i = 1;i <= n;++i)
	{
		f >> type >> value;
		if (type == 1)
			M.insert(value);
		else
			if (type == 2)
				M.erase(value);
			else
				if (M.find(value) != M.end())
					g << "1\n";
				else
					g << "0\n";


	}
	return 0;
}