对称二叉树

2025/10/16

思路：检查根节点的左右子树是不是相反的。

手写代码：

def isSymmetric(root):
    if root == None or (root.left == None and root.right == None):
        return True
    
    return isReverse(root.left, root_right)

def isReverse(root1, root2):
    if root1 == None and root2 == None:
        return True
    if (root1 == None and root != None) or (root1 != None and root == None):
    return False
    if root1.val != root2.val:
        return False
    return isReverse(root1.left, root2.right) and isReverse(root1.right, root2.left)

评价：完全正确，秒了