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 || (root.left == null && root.right == null)) return ;
17         TreeNode temp = root.left;
18         root.left = root.right;
19         root.right = temp;
20         if(root.left!=null) Mirror(root.left);
21         if(root.right!=null) Mirror(root.right);
22     }
23 }