#include<fstream>
#include<set>
using namespace std;
int main ()
{
	int n,i,x,y;
	set<int> s;
	ifstream fin("hashuri.in");
	ofstream fout("hashuri.out");
	fin>>n;
	for(i=1;i<=n;i++)
	{
		fin>>x>>y;
		if(x==1)
			s.insert(y);
		else
			if(x==2)
				s.erase(y);
			else 
				if(s.find(y)!=s.end()) fout<<1<<"\n";
				else fout<<0<<"\n";
	}
	fin.close();
	fout.close();
	return 0;
}