#include <fstream>
#include <map>
#include <unordered_map>

using namespace std;

ifstream f("hashuri.in");
ofstream g("hashuri.out");

int nr_op, op;

unordered_map<int, int> H;
int main()
{
    f>>nr_op;
    for(int i = 1 ; i <= nr_op ; ++i )
    {
        int tip, x;
        f>>tip>>x;
        if ( tip == 1 && H.find(x) == H.end() )
            H[x] = ++op;
        if ( tip == 2 )
            H.erase(x);
        if ( tip == 3 )
            g<<( H.find(x) != H.end() )<<'\n';
    }

    f.close();
    g.close();

    return 0;
}