#110
Balanced Binary Tree
easy · verified · 57.9% accepted · 12,141 likes · top 54%
tree · depth-first search · binary tree
Description
Given a binary tree, determine if it is height-balanced.
Example 1:
Input: root = [3,9,20,null,null,15,7]
Output: true
Example 2:
Input: root = [1,2,2,3,3,null,null,4,4]
Output: false
Example 3:
Input: root = []
Output: true
Solution