二叉树的镜像
题目描述:
操作给定的二叉树,将其变换为源二叉树的镜像。
代码实现:
# -*- coding:utf-8 -*-
# class TreeNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
class Solution:
# 返回镜像树的根节点
def Mirror(self, root):
# write code here
if root:
root.left,root.right = root.right,root.left
self.Mirror(root.left)
self.Mirror(root.right)
对称的二叉树
题目描述:
请实现一个函数,用来判断一颗二叉树是不是对称的。注意,如果一个二叉树同此二叉树的镜像是同样的,定义其为对称的。
代码实现:
# -*- coding:utf-8 -*-
# class TreeNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
class Solution:
def fun(self,node1,node2):
if not node1 and not node2:
return True
if node1 and node2 and node1.val == node2.val:
return self.fun(node1.left, node2.right) and self.fun(node1.right, node2.left)
return False
def isSymmetrical(self, pRoot):
# write code here
if not pRoot:
return True
return self.fun(pRoot.left,pRoot.right)
【补充】可以用对称的二叉树思路判断两个二叉树是否完全一致
def EqTree(self,TreeNode1,TreeNode2):
if not TreeNode1 and not TreeNode2:
return Ture
if TreeNode1 and TreeNode2 and TreeNode1.val == TreeNode2.val:
return Tree(TreeNode1.left,TreeNode2.left) and Tree(TreeNode1.right,TreeNode2.right)
else:
return False