[LeetCode]Binary Tree Right Side View
来源:互联网 发布:域名备案ps 编辑:程序博客网 时间:2024/05/16 11:25
Question:
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]
.
分析:
这道题是找到每一层最右边的那个节点, 所以可以想到用bsf。 bsf 使用的是queue,可以从右扫到左,第一个数字放进result里
易错点:
que的size要每次进入新的一层的时候申明
solution:
{code}
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public List<Integer> rightSideView(TreeNode root) {
ArrayList<Integer> res = new ArrayList<Integer>();
LinkedList<TreeNode> que = new LinkedList<TreeNode>();
if(root == null)
return res;
que.add(root);
while(!que.isEmpty()) {
int size = que.size();
for(int i=0;i<size;i++) {
TreeNode top = que.remove();
if(i==0) {
res.add(top.val);
}
if(top.right!=null) {
que.add(top.right);
}
if(top.left!=null) {
que.add(top.left);
}
}
}
return res;
}
}
{code}
/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */public class Solution { public List<Integer> rightSideView(TreeNode root) { ArrayList<Integer> res = new ArrayList<Integer>(); LinkedList<TreeNode> que = new LinkedList<TreeNode>(); if(root == null) return res; que.add(root); while(!que.isEmpty()) { int size = que.size(); for(int i=0;i<size;i++) { TreeNode top = que.remove(); if(i==0) { res.add(top.val); } if(top.right!=null) { que.add(top.right); } if(top.left!=null) { que.add(top.left); } } } return res; }}
- [leetcode][tree] Binary Tree Right Side View
- LeetCode OJ Binary Tree Right Side View
- LeetCode:Binary Tree Right Side View
- [leetcode] 199 Binary Tree Right Side View
- [LeetCode]199.Binary Tree Right Side View
- Leetcode: Binary Tree Right Side View
- LeetCode | Binary Tree Right Side View
- [LeetCode] Binary Tree Right Side View
- LeetCode: Binary Tree Right Side View
- [leetcode]48 Binary Tree Right Side View
- [leetcode] Binary Tree Right Side View
- leetcode-199 Binary Tree Right Side View
- [LeetCode]Binary Tree Right Side View
- 199Binary Tree Right Side View-LeetCode
- Binary Tree Right Side View--LeetCode
- [LeetCode]Binary Tree Right Side View
- [LeetCode 199]Binary Tree Right Side View
- leetcode: Binary Tree Right Side View
- PostGIS中命令的解释
- version (or platform)dependent Code
- 【Leetcode】Course Schedule #207
- java util包概述
- LA 3635 Pie 派
- [LeetCode]Binary Tree Right Side View
- 《Java面试试题》写一个两个线程之间的死锁
- UVa 11520 Fill the Square 填充正方形
- 开发日记——LastWord
- spring aop实现mysql读写分离(可用于SAE的mysql数据库)
- 【Leetcode】Contains Duplicate II #219
- 解决ansible官网访问特别慢的问题
- LA 3902 Network 网络
- GitHub gitignore官方文档翻译