#include <bits/stdc++.h>

using namespace std;
ifstream f("hashuri.in");
ofstream g("hashuri.out");
unordered_set<int> s;
int n, t, x;
int main()
{
    f >> n;
    for (int i = 1; i <= n; i++)
    {
        f >> t >> x;
        if (t == 1)
            s.insert(x);
        else if (t == 2)
            s.erase(x);
        else if (s.find(x) == s.end())
            g << "0\n";
        else
            g << "1\n";
    }
    return 0;
}