#include<fstream>
#include<set>
#define key 2000000
using namespace std;
set<int> s[key + 5];
int m, op, x;
int _list;
ifstream cin("hashuri.in");
ofstream cout("hashuri.out");
void hash_insert(int x)
{
    _list = x % key;
    if(s[_list].find(x) == s[_list].end())
    {
        s[_list].insert(x);
    }
}
void hash_erase(int x)
{
    _list = x % key;
    s[_list].erase(x);
}
void hash_query(int x)
{
    _list = x % key;
    if(s[_list].find(x) != s[_list].end())
    {
        cout << "1\n";
    }else
    {
        cout << "0\n";
    }
}

int main()
{
    cin >> m;
    while(m--)
    {
        cin >> op >> x;
        if(op == 1)
        {
            hash_insert(x);
            continue;
        }
        if(op == 2)
        {
            hash_erase(x);
            continue;
        }
        hash_query(x);
    }
    return 0;
}