https://clickhouse-test-reports.s3.yandex.net/17375/99073c26ee2692f8efe2ab14b2d8ae0fd813b80e/fuzzer/fuzzer.log

```
SELECT
    k,
    topK(v)
FROM 
(
    SELECT
        number % 7 AS k,
        arrayMap(x -> arrayMap(x -> if(x = 0, NULL, toString(x)), range(x)), range(intDiv(number, 1))) AS v
    FROM system.numbers
    LIMIT 257
)
GROUP BY k
ORDER BY k ASC
```
};
public:
    using key_type = Key;
    using mapped_type = typename Cell::mapped_type;
    using value_type = typename Cell::value_type;
    using cell_type = Cell;
    using LookupResult = Cell *;
    using ConstLookupResult = const Cell *;
    size_t hash(const Key & x) const { return Hash::operator()(x); }
    HashTable()
    {
        if (Cell::need_zero_value_storage)
            this->zeroValue()->setZero();
        alloc(grower);
    }
    HashTable(size_t reserve_for_num_elements)