solved https://www.e-olymp.com/en/problems/6033/statistics - 1

solved red black tree implementation - 2

• 2-3-4 tree
• Red Black tree

A skip list (structure) in two methods , representing a skip-list with two different implementations I've observed that a skip list looks similar to a balanced tree of similar height. so this can imply that a balanced tree can be simply flipped to represent a fast but more memory intense skip-list.

• Method (A) : ->skip list represented with fastrand() generated levels for the skiplist. ->must behave as a doubly linked list in absense of "levels" functionality.

• Method (B) : ->Flip a fully balanced tree , as in the case of red-black tree balancing.