#include<fstream>
#include<set>
#define key 1000
using namespace std;
ifstream cin("hashuri.in");
ofstream cout("hashuri.out");
set<int> s[key + 5];
int lista, x, op, n;
void insert_hash(int x)
{
    lista = x % key;
    if(s[lista].find(x) == s[lista].end())
    {
        s[lista].insert(x);
    }
}
void erase_hash(int x)
{
    lista = x % key;
    s[lista].erase(x);
}
void query_hash(int x)
{
    lista = x % key;
    if(s[lista].find(x) != s[lista].end())
    {
        cout << "1\n";
    }else
    {
        cout << "0\n";
    }
}
int main()
{
    cin >> n;
    for(;n--;)
    {
        cin >> op >> x;

        if(op == 1)
        {
            insert_hash(x);
            continue;
        }
        if(op == 2)
        {
            erase_hash(x);
            continue;
        }
        query_hash(x);
    }
    return 0;
}