public K[] getAllKeys()
{
List <K> r = new List <K>();
r.Add(key);
r.AddRange(left == null ? new K[0] : left.getAllKeys());
r.AddRange(right == null ? new K[0] : right.getAllKeys());
return(r.ToArray());
}
public K[] getAllKeys()
{
if (root == null)
{
return(new K[0]);
}
return(root.getAllKeys());
}