#include <fstream>
#include <set>

using namespace std;

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

multiset<unsigned> my_set;

unsigned N, x;
unsigned short op;

int main()
{
    in >> N;
    for(unsigned i = 1; i <= N; ++i)
    {
        in >> op >> x;
        switch(op) {
        case 1:
            if(my_set.find(x) == my_set.end())
                my_set.insert(x);
            break;
        case 2:
            my_set.erase(x);
            break;
        case 3:
            out << (my_set.find(x) != my_set.end() ? 1 : 0) << '\n';
            break;
        }
    }
    return 0;
}