#include <bits/stdc++.h>
using namespace std;
ifstream fin("hashuri.in");
ifstream fout("hashuri.out");
unordered_set<int> s;
int n, t, x;
int main()
{
    fin >> n;
    for ( ; n; n--)
    {
        fin >> t >> x;
        if (t == 1)
        {
            s.insert(x);
        }
        else if (t == 2)
        {
            s.erase(x);
        }
        else if (s.find(x) == s.end())
            fout << "0" << endl;
        else
            fout << 1 << endl;
    }

    return 0;
}