I have a 2 part question where I first had to illustrate a binary search tree given values that must be inserted in order: 11, 12, 15, 18, 16, 13, 14, 17.

From this i have the following diagram:

The second part of the question which is what i need help with requires me to minimise the search time of this binary search tree. This should be done using only left-hand and right-hand rotations and not using avl definitions as that is in a later question.

Describe each rotation and Illustrate the changed binary search tree after each rotation.