#include <iostream>
#include <fstream>
#include <unordered_map>

using namespace std;

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

int main()
{
    unordered_map <int, int> M;
    int n, option, x;
    f >> n;
    for (int i = 1; i <= n; i++)
    {
        f >> option >> x;
        switch (option)
        {
            case 1:
                M[x] = 1;
                break;
            case 2:
                M.erase(x);
                break;
            case 3:
                if (M.find(x) != M.end())
                {
                    g << "1\n";
                }
                else
                {
                    g << "0\n";
                }
                break;
        }
    }
}