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

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

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

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

    return 0;
}