#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <cstring>
#include <deque>
#include <algorithm>
#include <set>
#define Nmax 200005
#define INF 0x3f3f3f3f
#define ll long long
#define MOD 1999999973

using namespace std;

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

int n, op, x;
set <int> s;
set <int> ::iterator it;

int main()
{
    f >> n;

    while (n--)
    {
        f >> op >> x;
        if (op == 1)
        {
            s.insert(x);
        }
        else if (op == 2)
        {
            it=s.find(x);
            if (it!=s.end()) s.erase(it);
        }
        else if (op == 3)
        {
            if (s.find(x)!=s.end()) g << "1\n";
            else g << "0\n";
        }
    }

    return 0;
}