【剑指offer】十二，二叉树的镜像

 1 /**
 2 public class TreeNode {
 3     int val = 0;
 4     TreeNode left = null;
 5     TreeNode right = null;
 6  
 7     public TreeNode(int val) {
 8         this.val = val;
 9  
10     }
11  
12 }
13 */
14 public class Solution {
15      public void Mirror(TreeNode root) {
16             if(root==null){
17                 return ;
18             }
19             TreeNode temp  ;
20             temp = root.left ;
21             root.left = root.right ;
22             root.right = temp ;
23             Mirror(root.left) ;
24             Mirror(root.right) ;
25         }
26 }