#include<fstream>
#include<unordered_set>
using namespace std;
ifstream fi("hashuri.in");
ofstream fo("hashuri.out");

unordered_set <int> myHash;
int i,n,oper,x;

int main(){
	fi>>n;
	for(i=1;i<=n;i++){
					  fi>>oper>>x;	
					  if(oper==1) myHash.insert(x);
					  else if(oper==2) myHash.erase(x);
					  else if(oper==3){
					                   if(myHash.find(x)!=myHash.end()) fo<<"1\n";
					                   else fo<<"0\n";
					  				  }
					 }
	
	fi.close();
	fo.close();
	return 0;
}