剑指offer python版 28.对称的二叉树

"""
实现一个函数，判断一颗二叉树是不是对称的。
如果一个二叉树和它的镜像一样，那么它是对称的。
"""
class TreeNode:
    def __init__(self, x):
        self.val = x
        self.left = None
        self.right = None

class Solution:
    def isSymmetrical(self, pRoot):
        return self.isSymmetrical1(pRoot, pRoot)

    def isSymmetrical1(self, pRoot1, pRoot2):
        if pRoot1 == None and pRoot2 == None:
            return True
        if pRoot1 == None or pRoot2 == None:
            return False
        if pRoot1.val != pRoot2.val:
            return False
        return self.isSymmetrical1(pRoot1.left, pRoot2.right) and \
            self.isSymmetrical1(pRoot1.right, pRoot2.left)


if __name__ == "__main__":
    pNode1 = TreeNode(8)
    pNode2 = TreeNode(6)
    pNode3 = TreeNode(10)
    pNode4 = TreeNode(5)
    pNode5 = TreeNode(7)
    pNode6 = TreeNode(9)
    pNode7 = TreeNode(11)

    pNode1.left = pNode2
    pNode1.right = pNode3
    pNode2.left = pNode4
    pNode2.right = pNode5
    pNode3.left = pNode6
    pNode3.right = pNode7

    S = Solution()
    print(S.isSymmetrical(pNode1))