#include<fstream>
#include<set>


using namespace std;
ifstream fin("hashuri.in");
ofstream fout("hashuri.out");
set<int> s;
set<int>::iterator it;
int x,y,n,i;


int main()
{
	fin>>n;
	for(i=1;i<=n;i++)
	{
		fin>>x>>y;
		if(x==1)
			s.insert(y);
		if(x==2)
			s.erase (y);
		if (x==3){
			it=s.find(y);
			if(it!=s.end())
				fout<<"1"<<"\n";
			else fout<<"0"<<"\n";
		}
	}
return 0;
}