题解 | #二叉树的镜像#
二叉树的镜像
https://www.nowcoder.com/practice/a9d0ecbacef9410ca97463e4a5c83be7
import java.util.*; /* * public class TreeNode { * int val = 0; * TreeNode left = null; * TreeNode right = null; * public TreeNode(int val) { * this.val = val; * } * } */ public class Solution { /** * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可 * * * @param pRoot TreeNode类 * @return TreeNode类 */ public TreeNode Mirror (TreeNode pRoot) { if(pRoot == null){ return null; } //临时变量存右子树 TreeNode temp = pRoot.right; //先一直往左子树递归,递归到叶子节点后返回 pRoot.right = Mirror(pRoot.left); pRoot.left = Mirror(temp); return pRoot; } }