#include<fstream>
#include<set>

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

int N;
set<int> A;

int main()
{
    fin >> N;
    int op, x;
    for(int i = 1; i <= N; i++)
    {
        fin >> op >> x;

            if(op == 1)
                A.insert(x);

            if(op == 2)
                A.erase(x);

            if(op == 3)
            {
                if(*A.find(x) == *A.end())
                    fout << 0 <<'\n';
                else
                    fout << 1 <<'\n';
            }


    }
    fin.close();
    return 0;
}