image.png
典型的递归题
先递归到左叶子节点，再递归到右叶子节点，然后再交换，直接上图
image.png
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
class Solution {
public TreeNode invertTree(TreeNode root) {
if(root==null||(root.left==null&&root.right==null)) return root;
TreeNode left=invertTree(root.left);
TreeNode right=invertTree(root.right);
root.left=right;
root.right=left;
return root;
}
}
网友评论