牛客网-二叉树的镜像

曾经终败给现在 2023-03-01 09:40 3阅读 0赞

# 题目描述 #

操作给定的二叉树，将其变换为源二叉树的镜像。  
输入描述:  
二叉树的镜像定义：源二叉树  
8  
/  
6 10  
/ \\ /  
5 7 9 11  
镜像二叉树  
8  
/  
10 6  
/ \\ /  
11 9 7 5

牛客网OJ连接：[https://www.nowcoder.com/practice/564f4c26aa584921bc75623e48ca3011][https_www.nowcoder.com_practice_564f4c26aa584921bc75623e48ca3011]

力扣连接：[https://leetcode-cn.com/problems/er-cha-shu-de-jing-xiang-lcof/submissions/][https_leetcode-cn.com_problems_er-cha-shu-de-jing-xiang-lcof_submissions]

# 解题 #

/** public class TreeNode { int val = 0; TreeNode left = null; TreeNode right = null; public TreeNode(int val) { this.val = val; } } */
    public class Solution { 
        public void Mirror(TreeNode root) { 
            if(root==null)
                return;
            //就是一个交换的过程
            TreeNode temp = root.left;
            root.left = root.right;
            root.right = temp;
            
            Mirror(root.left);
            Mirror(root.right);
        }
    }

/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */
    class Solution { 
        public TreeNode mirrorTree(TreeNode root) { 
            if(root==null)
                return root;
            
            TreeNode temp = root.left;
            root.left = root.right;
            root.right = temp;
            mirrorTree(root.left);
            mirrorTree(root.right);
    
            return root;
        }
    }

[https_www.nowcoder.com_practice_564f4c26aa584921bc75623e48ca3011]: https://www.nowcoder.com/practice/564f4c26aa584921bc75623e48ca3011
[https_leetcode-cn.com_problems_er-cha-shu-de-jing-xiang-lcof_submissions]: https://leetcode-cn.com/problems/er-cha-shu-de-jing-xiang-lcof/submissions/