226. Invert Binary Tree
Easy
Given the root of a binary tree, invert the tree, and return its root.
Example 1:
Example 2:
Example 3:
Constraints:
- The number of nodes in the tree is in the range [0, 100].
- -100 <= Node.val <= 100
Solution
class Solution:
def invertTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]:
if root is None:
return None
return TreeNode(
root.val, self.invertTree(root.right), self.invertTree(root.left)
)
class TreeNode:
def __init__(self, val=0, left=None, right=None):
self.val = val
self.left = left
self.right = right