LeetCode #101: Symmetric Tree
β’ 85 words β’ 1 min β’ updated
LeetCode #101: Symmetric Tree:
python
# 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 isSymmetric(self, root: Optional[TreeNode]) -> bool:
if root is None:
return True
def mirror(left, right):
if left is None and left is None:
return True
if left is None or right is None:
return False
if left.val != right.val:
return False
return mirror(left.left, right.right) and mirror(left.right, right.left)
return mirror(root.left, root.right)