Given a binary tree, determine if it is height-balanced.
For this problem, a height-balanced binary tree is defined as:
a binary tree in which the depth of the two subtrees of every node never differ by more than 1.
Given the following tree [3,9,20,null,null,15,7]:
3 / \ 9 20 / \ 15 7 Return true.
Given the following tree [1,2,2,3,3,null,null,4,4]:
1 / \ 2 2 / \ 3 3 / \ 4 4 Return false.
# Definition for a binary tree node.# class TreeNode:# def __init__(self, x):# self.val = x# self.left = None# self.right = NoneclassSolution: defisBalanced(self, root: TreeNode) ->bool: defdepth(root: TreeNode) ->int: ifnotroot: return0ldepth=depth(root.left) rdepth=depth(root.right) ifldepth==-1orrdepth==-1orabs(ldepth-rdepth) >1: return-1returnmax(ldepth, rdepth) +1returndepth(root) !=-1