#include <fstream>
#include <set>

using namespace std;

ifstream F ("hashuri.in");
ofstream G ("hashuri.out");

set < int > s;
int op, n, x;

int main()
{
    F >> n;
    for(int i = 0; i < n; ++ i)
    {
        F >> op >> x;
        if (op == 1)
        {
            if (s.find(x) == s.end())
                s.insert(x);
        }
        else
            if(op == 2)
            {
                if (s.find(x) != s.end())
                    s.erase(s.find(x));
            }
            else
                if(op == 3)
                {
                    if (s.find(x) != s.end())
                        G << "1\n";
                    else
                        G << "0\n";
                }
    }
    return 0;
}