110. Balanced Binary Tree
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.
Solution:
class Solution(object):
def isBalanced(self, root):
"""
:type root: TreeNode
:rtype: bool
"""
def depth(node):
if not node:
return 0
left = depth(node.left)
right = depth(node.right)
if left < 0 or right < 0 or abs(left - right) > 1:
return -1
return max(left, right) + 1
return depth(root) >= 0