思路也很简单,就是后续遍历的同时把所有的左右节点换一下位置就 ok. 代码如下: 123456789class Solution: def invertTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]: if root is None: return left = self.invertTree(root.left) right = self.invertTree(root.right) root.left = right root.right = left return root