LeetCode-翻转二叉树(Java)

题目链接

Problem.226:https://leetcode.com/problems/invert-binary-tree/

题目描述

	翻转二叉树

示例

	输入: 
			 4
		   /   \
		  2     7
		 / \   / \
		1   3 6   9
	输出:
		     4
		   /   \
		  7     2
		 / \   / \
		9   6 3   1

解析

	public TreeNode invertTree(TreeNode root) {
    	if(root == null) return null;
    	TreeNode left = root.left;
    	root.left = invertTree(root.right);
    	root.right = invertTree(left);
    	return root;
	}