AVL Tree
Detailed guide and Python implementation for the 'AVL Tree' problem.
Problem Statement
Write a function is_avl_balanced(tree_arr) that takes an array representation of a binary tree tree_arr and returns True if the tree is height-balanced (for every node, the height of its left and right subtrees differs by at most 1) and is a valid BST, or False otherwise.
- •0 <= len(tree_arr) <= 1000
Examples
tree_arr = [3, 9, 20, None, None, 15, 7]
True
The tree is a valid BST and the depth difference of left/right subtrees of all nodes is at most 1.
tree_arr = [1, 2, None, 3, None, None, None, 4]
False
The tree is unbalanced because leaf node 4 is at depth 4 while right subtree of node 1 is empty.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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