#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
#define pb push_back
#define po pop_back

ifstream fin("hashuri.in");
ofstream fout("hashuri.out");

int main()
{
    unordered_set<int> x;

    int q;
    fin >> q;
    int n, tmp;
    while (q--)
    {
        fin >> n >> tmp;
        if (n == 1)
        {
            x.insert(tmp);
        }
        else if (n == 2)
        {
            x.erase(tmp);
        }
        else
        {
            if (x.count(tmp) == 1)
            {
                fout << 1 << '\n';
            }
            else
                fout << 0 << '\n';
        }
    }
}