//      hash.cpp
//      
//      Copyright 2010 SpeeDemon <virtualdemon@ubuntu>
//      
//      This program is free software; you can redistribute it and/or modify
//      it under the terms of the GNU General Public License as published by
//      the Free Software Foundation; either version 2 of the License, or
//      (at your option) any later version.
//      
//      This program is distributed in the hope that it will be useful,
//      but WITHOUT ANY WARRANTY; without even the implied warranty of
//      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//      GNU General Public License for more details.
//      
//      You should have received a copy of the GNU General Public License
//      along with this program; if not, write to the Free Software
//      Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
//      MA 02110-1301, USA.
#include <hash_set.h>
#include <fstream>
 
/*
 * 
 */
using namespace std;
using namespace __gnu_cxx;
hash_set< int, hash<int> > v;
int main()
{int n, x, y;
    ifstream in("hashuri.in");
    ofstream out("hashuri.out");
    in>>n;
    for( ; n; --n )
    {
        in>>x>>y;
        switch( x )
        {
            case 1: v.insert(y); break;
            case 2: v.erase(y); break;
            case 3: out<<( v.end() != v.find(y))<<'\n'; break;
        }
    }
    return 0;
}