题干 Bob is very interested in the data structure of a tree. A tree is a directed graph in which a special node is singled out, called the "root" of the tree, and there is a unique path from the root to each of the other nodes. Bob intends to colo…

贪心....                    Color a Tree Time Limit: 1000MS   Memory Limit: 30000K Total Submissions: 6647   Accepted: 2249 Description Bob is very interested in the data structure of a tree. A tree is a directed graph in which a special node is single…

# include <stdio.h> # include <algorithm> # include <string.h> using namespace std; int father[1010]; int next[1010];//当前集合的下个元素(包含i) int pre[1010];//当前集合的上个元素(包含i) int num[1010];//num[i]当前集合储存的点的个数(包含i) int vis[1010]; int sum[1010];//当前…

题目链接 代码借鉴此博:http://www.cnblogs.com/vongang/archive/2011/08/19/2146070.html 其中关于max{c[fa]/t[fa]}贪心原则,此博有很好的解释:http://www.cnblogs.com/rainydays/p/3271277.html 在此引用其中几段话: 试想,如果没有父节点排在节点之前的限制,那么这个题目非常简单,只需要将结点按照权值从大到小排列即可.加上了这个限制之后,如果权值最大的那个节点一旦满足了条件(父节点…

$ POJ~2054~Color~a~Tree $ $ solution: $ 我们先从题中抽取信息,因为每个点的费用和染色的次数有关,所以我们可以很自然的想到先给权值大的节点染色.但是题目还说每个节点染色前它的父亲节点也必须被染色,这就有了很多的后效性. 暂时没有办法贪心,我们就只能再找找性质.博主首先想到的是从叶子节点考虑,叶子节点里权值最小的一定最后染色.但是经过自我hack,这个结论也是错的.举个栗子:5-1-1-1-8,这条链上如果以左边第一个1为根,先染5会更优. 叶子节点我们拿他没…

[LeetCode]863. All Nodes Distance K in Binary Tree 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/all-nodes-distance-k-in-binary-tree/description/ 题目描述: We are given a binary tree (with root no…

[LeetCode]297. Serialize and Deserialize Binary Tree 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/serialize-and-deserialize-binary-tree/description/ 题目描述: Serialization is the process of converting a data structure or object into a se…

[LeetCode]331. Verify Preorder Serialization of a Binary Tree 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/verify-preorder-serialization-of-a-binary-tree/description/ 题目描述: One way to serialize a binary tree is to use pre-order traver…

[LeetCode]109. Convert Sorted List to Binary Search Tree 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.me/ 题目地址:https://leetcode.com/problems/convert-sorted-list-to-binary-search-tree/description/ 题目描述: Given a s…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址:https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/description/ 题目描述 Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in…