### Chapter 20 AVL Trees

*20.1*The _________ of a node is the height of its right subtree minus the height of its left subtree.

*20.2*The balance factor of every node in an AVL tree may be _________.

*20.3*A __________ (with no duplicate elements) has the property that for every node in the tree the value of any node in its left subtree is less than the value of the node and the value of any node in its right subtree is greater than the value of the node.

*20.4*The time complexity for insertion, deletion, and search is O(logn) for a ___________.

*20.5*In a ________, the element j to be removed is always at the root.

*20.6*In a ________, the element just inserted is always at the leaf.

*20.7*The average time-complexity for insertion, deletion, and search in a ________ is O(logn).