Lesson 1

Question 1

Named after their inventor_, _are height balancing binary search tree. _ checks the height of the left and the right sub-trees and assures that the difference is not more than 1. This difference is called the Balance Factor.

Answer 1

Adelson- Velski & Landis
AVL trees

Question 2

AVL Rotations
To balance itself, an AVL tree may perform the following four kinds of rotations −

Answer 2

• Left rotation
• Right rotation
• Left-Right rotation
• Right-Left rotation

Question 3

If a tree becomes unbalanced, when a node is inserted into the right subtree of the right subtree.

Answer 3

LEFT ROTATION

Question 4

AVL tree may become unbalanced, if a node is inserted in the left subtree of the left subtree.

Answer 4

RIGHT ROTATION

Question 5

Double rotations are slightly complex version of already explained versions of rotations. To understand them better, we should take note of each action performed while rotation.

Answer 5

LEFT-RIGHT ROTATION

Question 6

The second type of double rotation is _ Rotation. It is a combination of right rotation followed by left rotation.

Answer 6

RIGHT-LEFT ROTATION