#include<fstream>
 #include<set>
 #define LL long long
 using namespace std;
 ifstream cin("hashuri.in");
 ofstream cout("hashuri.out");
 LL N,X;
 set<LL> T; 
 int op;
 int main() {
 	 LL i;
 	    cin>>N;
 	    for(i=1;i<=N;i++)  {
 	           cin>>op>>X;
 	           switch(op) {
			  case 1 : T.insert(X); break;
			  case 2 : T.erase(X); break;
			  case 3 : if (T.find(X)!=T.end()) cout<<1<<"\n";
			                 else cout<<0<<"\n";
						break;
						}
			}
	return 0;
}