#include <fstream>
#include <map>

using namespace std;

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

int t, nr, cer, x;
map <int, int> a;

int main()
{
    for (f >> t; t; t--)
    {
        f >> cer >> x;
        if (cer == 1 && a.find(x) == a.end())
            a[x] = 1;
        else if (cer == 2)
            a.erase(x);
        else if (cer == 3)
            g << (a.find(x) != a.end()) << '\n';
    }
    return 0;
}