#include <fstream>
#include <set>
using namespace std;
ofstream fout ("hashuri.out");
ifstream fin ("hashuri.in");
set < int > s;
int n,a,b;
int main()
{
    fin>>n;
    while( n-- )
    {
        fin>>a>>b;
        if( a == 1 )
            s.insert( b );
        if( a == 2 && s.find( b ) != s.end() )
            s.erase( b );
        if( a == 3 )
            fout<<( s.find( b ) != s.end() ? '1' : '0')<<'\n' ;
    }
    return 0;
}