private HashTreeV2(int key, V value, HashTreeV2 <V> left, HashTreeV2 <V> right)
{
Key = key;
Value = value;
Left = left;
Right = right;
Height = 1 + (left.Height > right.Height ? left.Height : right.Height);
}
private HashTreeV2 <V> With(HashTreeV2 <V> left, HashTreeV2 <V> right)
{
return(new HashTreeV2 <V>(Key, Value, left, right));
}