#include <fstream>
#include <map>

using namespace std;

unsigned int N;
unsigned short int op;
unsigned int x;

map < unsigned int, unsigned int > M;
unsigned int i, NR;

int main ()
{
    ifstream fin ("hashuri.in");
    fin >> N;
    ofstream fout ("hashuri.out");
    for (i=1; i<=N; i++)
    {
        fin >> op >> x;
        if (op == 1 && M.find(x)==M.end())
        {
            NR++;
            M[x] = NR;
        }
        else if (op == 2)
            M.erase(x);
        else
            fout << (M.find(x)!=M.end()) << '\n';
    }
    fin.close();
    fout.close();
    return 0;
}