#include <bits/stdc++.h>
using namespace std;
ifstream f ("hashuri.in");
ofstream g ("hashuri.out");
unordered_map <int, bool> m;
int n;
int main()
{
    f>>n;
    for (int p, x, i = 1; i <= n; i++)
    {
        f>>p>>x;
        if (p == 1) m[x] = 1;
        else if (p == 2) m.erase(x);
        else g<<(m.find(x) != m.end())<<'\n';
    }
    return 0;
}