4. Trees and Tries
Table of Contents
226. Invert Binary Tree
Given the root of a binary tree, invert the tree, and return its root.
Key Ideas
Code
# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, val=0, left=None, right=None):
# self.val = val
# self.left = left
# self.right = right
class Solution:
def invertTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]:
if root is None or root.left == None and root.right == None:
return root
root.left, root.right = root.right, root.left
self.invertTree(root.left)
self.invertTree(root.right)
return root