#include <iostream>
#include <fstream>
#include <set>

using namespace std;

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

int main()
{
    set <int> Set;
    int n;
    f >> n;
    for (int i = 1; i <= n; i++)
    {
        int option, x;
        f >> option >> x;
        switch (option)
        {
            case 1:
                Set.insert(x);
                break;
            case 2:
                Set.erase(x);
                break;
            case 3:
                bool ok = false;
                for (auto i = Set.begin(); i != Set.end(); i++)
                {
                    if (*i == x)
                    {
                        g << "1\n";
                        ok = true;
                        break;
                    }
                }
                if (ok == false)
                {
                    g << "0\n";
                }
                break;
        }
    }
}