题目描述
给你一棵二叉树的根节点 root ,翻转这棵二叉树,并返回其根节点。
代码
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode() {}
* TreeNode(int val) { this.val = val; }
* TreeNode(int val, TreeNode left, TreeNode right) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
class Solution {
//翻转以root为根节点的树,并返回其根节点
public TreeNode invertTree(TreeNode root) {
if(root==null) return null;
TreeNode t = root.left;
root.left = invertTree(root.right); //左子节点换成右子节点
root.right = invertTree(t); //右子节点换成左子节点
return root;
}
}