#include<fstream>
#include<set>

using namespace std;

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

int N,i,x,c;

int main()
{
	multiset <int> my_set;
	fin>>N;
	for(i=1;i<=N;++i)
	{
		fin>>c>>x;
		switch(c)
		{
			case 1:{
				if(my_set.find(x)==my_set.end())my_set.insert(x);
				break;
			}
			case 2:{
				if(my_set.find(x)!=my_set.end())my_set.erase(my_set.find(x));
				break;
			}
			default:{
				if(my_set.find(x)!=my_set.end())fout<<"1\n";
				else fout<<"0\n";
				break;
			}
		}
	}
 	return 0;
}