#include <fstream>
#include <unordered_map>
using namespace std;
ifstream f("hashuri.in");
ofstream g("hashuri.out");
int main()
{
    int n, k, v;
    unordered_map <int, int> map;
    f >> n;
    for (int c = 0; c < n; c++)
    {
        f >> k >> v;
        switch (k)
        {
            case 1:
                if (!map.count(v))
                {
                    map[v] = 1;
                }
                break;
            case 2:
                map.erase(v);
                break;
            case 3:
                if (map.count(v))
                {
                    g << 1 << "\n";
                    break;
                }
                g << 0 << "\n";
                break;
        }
    }
    return 0;
}