#include <bits/stdc++.h>
using namespace std;

ifstream f("hashuri.in");
ofstream g("hashuri.out");

map <int, int> m;
int t, var;
int main()
{
    f >> t;
    while(t--)
    {
        int op, x;
        f >> op >> x;
        if(op == 1 && m.find(x) == m.end()) m[x] = ++ var;
        if(op == 2) m.erase(x);
        if(op == 3) g << (m.find(x) != m.end()) << '\n';

    }
    return 0;
}