563. 二叉树的坡度

缺乏、安全感 2022-11-22 05:28 79阅读 0赞

# 题目来源 #

[563. 二叉树的坡度][563.]

# 题目来源 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poaXpoZW5nZ3Vhbg_size_16_color_FFFFFF_t_70_pic_center]

# 题目解析 #

关键是看懂题目

/**
     * 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 {
        
        private int tilt = 0;
        public int findTilt(TreeNode root) {
        
            if (root == null){
        
                return 0;
            }
    
            helper(root);
            return tilt;
        }
    
        public int helper(TreeNode root) {
        
            if (root == null){
        
                return 0;
            }
            
            int left = helper(root.left);
            int right = helper(root.right);
            
            tilt+=Math.abs(left-right);
            
            return left + right + root.val;
        }
    }

![在这里插入图片描述][20201103195205251.png_pic_center]

[563.]: https://leetcode-cn.com/problems/binary-tree-tilt/submissions/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poaXpoZW5nZ3Vhbg_size_16_color_FFFFFF_t_70_pic_center]: https://img-blog.csdnimg.cn/20201103195311835.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poaXpoZW5nZ3Vhbg==,size_16,color_FFFFFF,t_70#pic_center
[20201103195205251.png_pic_center]: https://img-blog.csdnimg.cn/20201103195205251.png#pic_center