#include <fstream>
#include <set>

using namespace std;

ifstream cin("hashuri.in") ;
ofstream cout("hashuri.out") ;

set <int> A ;


int main()
{
    int op , X ;

    for(int i = 1; i <= N; ++ i)
    {
        cin  >> op >> X ;
        if(op == 1)
        {
            A.insert(X) ;
            continue ;
        }
        if(op == 2)
        {
            A.erase(X) ;
            continue ;
        }
        if(op == 3)

            if(A.find(X) != A.end())

                cout << 1;
            else 0 ;


    }
    cin.close() ;
    cout.close() ;
    return 0;
}