The height of a red-black BST with N nodes is no more than 2lgN.
The average length of a path from the root to a node in a red-black BST with N nodes is ~lgN.
In a red-black BST, the following operations take logarithmic time in the worst case:
search, insertion, finding the minimum, finding the maximum, floor, ceiling, rank, select,
delete the minimum, delte the maximum, delete, ad range count.
