#include <iostream>
#include <fstream>
#include <map>

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

int N,op,x;
map <int,int> M;

int main()
{
    f >> N;
     for (int i=1; i<=N ; i++)
     {
         f >> op >> x;
         if (op == 1 && M.find(x) == M.end()) M[x] = 1;
         if (op == 2 ) M.erase(x);
         if (op == 3 ) g << (M.find(x) != M.end()) << '\n';
         }

    return 0;
}