[LeetCode] 199.Binary Tree Right Side View 二叉树的右侧视图
Given a binary tree, imagine yourself standing on the right side of it, return the values of the nodes you can see ordered from top to bottom.
For example:
Given the following binary tree,
1 <---
/ \
2 3 <---
\ \
5 4 <---
You should return [1, 3, 4].
Credits:
Special thanks to @amrsaqr for adding this problem and creating all test cases.
这道题要求我们打印出二叉树每一行最右边的一个数字,实际上是求二叉树层序遍历的一种变形,我们只需要保存每一层最右边的数字即可,可以参考我之前的博客 Binary Tree Level Order Traversal 二叉树层序遍历,这道题只要在之前那道题上稍加修改即可得到结果,还是需要用到数据结构队列queue,遍历每层的节点时,把下一层的节点都存入到queue中,每当开始新一层节点的遍历之前,先把新一层最后一个节点值存到结果中,代码如下:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
|
/** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public : vector< int > rightSideView(TreeNode *root) { vector< int > res; if (!root) return res; queue<TreeNode*> q; q.push(root); while (!q.empty()) { res.push_back(q.back()->val); int size = q.size(); for ( int i = 0; i < size; ++i) { TreeNode *node = q.front(); q.pop(); if (node->left) q.push(node->left); if (node->right) q.push(node->right); } } return res; } }; |
到此这篇关于C++实现LeetCode(199.二叉树的右侧视图)的文章就介绍到这了,更多相关C++实现二叉树的右侧视图内容请搜索服务器之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持服务器之家!
原文链接:https://www.cnblogs.com/grandyang/p/4392254.html