#include <fstream>
#include <set>
using namespace std;
ifstream fin("hashuri.in");
ofstream fout("hashuri.out");

int main()
{
    int t, op, val;
    fin >> t;
    set<int> s;
    while (t-- > 0)
    {
        fin >> op >> val;
        if (op == 1)
        {
            s.insert(val);
        }
        else if (op == 2)
        {
            s.erase(val);
        }
        else if (op == 3)
        {
            fout << ((s.find(val) != s.end()) ? 1 : 0) << "\n";
        }
    }
    return 0;
}