题目:
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题解:
python
class Solution:
def isBalanced(self, root: TreeNode) -> bool:
def height(root: TreeNode) -> int:
if not root:
return 0
leftHeight = height(root.left)
rightHeight = height(root.right)
if leftHeight == -1 or rightHeight == -1 or abs(leftHeight - rightHeight) > 1:
return -1
else:
return max(leftHeight, rightHeight) + 1
return height(root) >= 0