- class Solution:
- def flatten(self, root: Optional[TreeNode]) -> None:
- while root:
- if root.left:
- sub_left=root.left
- while sub_left.right:
- sub_left=sub_left.right
- sub_left.right=root.right
- root.right=root.left
- root.left=None
- root=root.right
移花接木大法
移花接木大法