#include <bits/stdc++.h>
#define in "hashuri.in"
#define out "hashuri.out"
using namespace std;
ifstream fin(in);
ofstream fout(out);

int n,nr = 0;
map <int,int> M;

int main()
{
    int i,op,x;

    fin >> n;
    for (i = 1; i <= n; i++)
    {
        fin >> op >> x;

        if (op == 1 && M.find(x) == M.end()) M[x] = ++nr;
        else if (op == 2) M.erase(x);
        else
        {
            if (M.find(x) != M.end()) fout << "1\n";
            else fout << "0\n";
        }
    }

    fin.close();
    fout.close();
    return 0;
}