#include <iostream>
#include <fstream>
#include <unordered_map>

using namespace std;

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

unordered_map<int, int> elements;

class query {
    private:
        short task;
        int x;

        void task1()
        {
            elements[x]++;
        }

        void task2()
        {
            if (elements[x]) elements[x]--;
        }

        void task3()
        {
            fout<<(bool)elements[x]<<'\n';
        }
    
    public:
        void read()
        {
            fin>>task>>x;
        }

        void solve()
        {
            if (task == 1) task1();
            if (task == 2) task2();
            if (task == 3) task3();
        }
};

int main()
{
    int n;
    query q;
    fin>>n;

    while (n--) q.read(), q.solve();

    return 0;
}