#include <fstream>
#include <set>

using namespace std;

ifstream fin("hashuri.in");
ofstream fout("hashuri.out");

int N, i, op, x;
set<int> sir;

int main()
{
    fin >> N;
    for (i=1; i<=N; i++)
    {
        fin >> op >> x;
        if (op==1)
          sir.insert(x);
        if (op==2)
          sir.erase(x);
        if (op==3)
        {
            if (sir.find(x)!=sir.end())
              fout << "1\n";
            else
              fout << "0\n";
        }
    }
    fin.close();
    fout.close();
    return 0;
}