题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=4123 Time Limit: 5000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) 问题描述 Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are…

Bob’s Race Time Limit: 5000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1994    Accepted Submission(s): 619 Problem Description Bob wants to hold a race to encourage people to do sports. He has got trouble i…

C - Bob’s Race Time Limit:2000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 4123   Description Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are N…

Bob’s Race Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=4123 Description Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are N houses and N - 1 roads…

Bob’s Race Time Limit: 5000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Problem Description Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are N houses and N - 1 roads…

题目链接 Problem Description Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are N houses and N - 1 roads in his village. Each road connects two houses, and all houses are connected together. To…

Bob’s Race Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=4123 Description Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are N houses and N - 1 roads…

题意是说给出一棵树,N(10^5)个顶点,以及每条边的权值,现在需要选择连续的K个点(顶点编号连续),可以被选出来的条件是: 若d[i]代表顶点i到树上其他点的距离的最大值,使得区间[a, b]的d值的最大差值不大于Q, 也就是max(d[a], d[a + 1], ..., d[b]) - max(d[a], d[a + 1], ..., d[b]) <= Q Q是给出的一个查询(共有m<=500个查询),求对应每一个查询的K的最大值 思路是首先预处理出每个点到其他点的最大距离, 这可以通过…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4123 题意: 给你一棵树,n个节点,每条边有长度. 然后有m个询问,每个询问给定一个q值. 设dis[i]为:从节点i出发,不重复经过节点,所能够走的最远距离. 每次询问问你:区间[l,r]最长能有多长,同时保证 max{dis[i]} - min{dis[i]} <= q (i∈[l,r]) 题解: 首先有一个结论: 从树上的任意一个节点出发,尽可能往远走,最终一定会到达树的直径的两个端点之一.…

题意: 给定n个点的带边权树Q个询问. 以下n-1行给出树 以下Q行每行一个数字表示询问. 首先求出dp[N] :dp[i]表示i点距离树上最远点的距离 询问u, 表示求出 dp 数组中最长的连续序列使得序列中最大值-最小值 <= u,输出这个序列的长度. 思路: 求dp数组就是求个树的直径然后dfs一下. 对于每一个询问,能够用一个单调队列维护一下.O(n)的回答. #include <cstdio> #include <cstring> #include <stri…

http://acm.hdu.edu.cn/showproblem.php? pid=4123 Problem Description Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are N houses and N - 1 roads in his village. Each road connects two houses,…

湫湫系列故事——设计风景线 Time Limit: 6000/3000 MS (Java/Others)    Memory Limit: 65535/32768 K (Java/Others)Total Submission(s): 4539    Accepted Submission(s): 816 Problem Description 随着杭州西湖的知名度的进一步提升,园林规划专家湫湫希望设计出一条新的经典观光线路,根据老板马小腾的指示,新的风景线最好能建成环形,如果没有条件建成环形,…

[HDU 5293]Tree chain problem(树形dp+树链剖分) 题面 在一棵树中,给出若干条链和链的权值,求选取不相交的链使得权值和最大. 分析 考虑树形dp,dp[x]表示以x为子树的最大权值和(选的链都在i的子树中) 设sum[x]表示x的儿子的dp值和,即\(\sum _{y \in \mathrm{son}(x)} dp[y]\) 1.不选两端点lca为x的链,dp[x]=sum[x] 2.选两端点lca为x的链,则dp[x]=max{链的权值+链上节点的所有子节点dp的…

Alice and Bob's Trip Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 2643    Accepted Submission(s): 708 Problem Description Alice and Bob are going on a trip. Alice is a lazy girl who wants to…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4123 参考博客:两种解法-树形dp+二分+单调队列(或RMQ)-hdu-4123-Bob’s Race - cc_again的专栏 - CSDN博客  https://blog.csdn.net/cc_again/article/details/12011757 题意:给出一棵有n个点的树,每条树边都有一个权值,对于每一个点,它都有一个编号,我们取它到其他点的最大距离记录下来,现在q个询问,每个询问…

Walking Race Time Limit: 10000MS   Memory Limit: 131072K Total Submissions: 4123   Accepted: 1029 Case Time Limit: 3000MS Description flymouse’s sister wc is very capable at sports and her favorite event is walking race. Chasing after the championshi…

给出一棵树,编号为1~n,给出数m 漂亮mm连续n天锻炼身体,每天会以节点i为起点,走到离i最远距离的节点 走了n天之后,mm想到知道自己这n天的锻炼效果 于是mm把这n天每一天走的距离记录在一起,成为一段长度为n的数列 现在mm想要从这数列中选出一个连续的区间,要求这个区间的max-min<=m 输出最长的区间 做了一个下午 思路: 分成2个部分: 1.求出数列,即对于一棵树,求出每一个节点能到达的最远距离 2.对于这段数列,选出一个区间,使得区间的max-min<=m,并且使得区间长度尽量…

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=5293 题意: 给你一些链,每条链都有自己的价值,求不相交不重合的链能够组成的最大价值. 题解: 树形dp, 对于每条链u,v,w,我们只在lca(u,v)的顶点上处理它 让dp[i]表示以i为根的指数的最大值,sum[i]表示dp[vi]的和(vi为i的儿子们) 则i点有两种决策,一种是不选以i为lca的链,则dp[i]=sum[i]. 另一种是选一条以i为lca的链,那么有转移方程:dp[i]=…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4003 Humans have discovered a kind of new metal mineral on Mars which are distributed in point‐like with paths connecting each of them which formed a tree. Now Humans launches k robots on Mars to collect…

[题目链接] http://acm.hdu.edu.cn/showproblem.php?pid=5758 [题目大意] 给出一棵树,每条路长度为1,允许从一个节点传送到任意一个节点,现在要求在传送次数尽量少的情况下至少经过每条路一遍啊,同时最小化走过的路程总长度.输出路程总长度. [题解] 首先,对于传送次数尽量少这个条件,我们很容易发现,当且仅当每次出发点和终止点都是叶节点的时候,是最少的,当然在叶节点无法两两匹配的时候,再多走一条链. 然后就是叶节点的匹配问题,使得匹配后的叶节点连线覆盖全…

Bob’s Race Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 378   Accepted: 119 Description Bob wants to hold a race to encourage people to do sports. He has got trouble in choosing the route. There are N houses and N - 1 roads in his vil…

Problem Description Bob enjoys playing computer games, especially strategic games, but sometimes he cannot find the solution fast enough and then he is very sad. Now he has the following problem. He must defend a medieval city, the roads of which for…

Colorful Tree Time Limit: 6000/3000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)Total Submission(s): 1539    Accepted Submission(s): 616 Sample Input 3 1 2 1 1 2 2 3 6 1 2 1 3 2 1 1 2 1 3 2 4 2 5 3 6 Sample Output Case #1: 6 Case #…

Bob’s Race Time Limit: 5000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 3034    Accepted Submission(s): 991 Problem Description Bob wants to hold a race to encourage people to do sports. He has got trouble…

Strategic Game Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 10035    Accepted Submission(s): 4691 Problem Description Bob enjoys playing computer games, especially strategic games, but some…

POJ - 3162Walking Race 题目大意:有n个训练点,第i天就选择第i个训练点为起点跑到最远距离的点,然后连续的几天里如果最远距离的最大值和最小值的差距不超过m就可以作为观测区间,问这样的区间最长的长度? 一开始楞是没看懂题意,最讨厌这种四级题,这是在刁难我英语小能手(能用翻译的就不自己动手).而且这题感觉单调队列那里的处理更难一点,不过还是来说一说怎么树形dp取得最远距离,先画个简简单单丑丑的图 我们直接从1作为根节点开始dfs的话,可以处理1的最远距离,并且可以得出到其它节点…

题目描述 Walking RaceTime Limit: 10000MS Memory Limit: 131072KTotal Submissions: 4941 Accepted: 1252Case Time Limit: 3000MS Description flymouse's sister wc is very capable at sports and her favorite event is walking race. Chasing after the championship…

题意:有n个人,他们的关系,形成一棵有根树(0是树根,代表管理员),每个人有一个价值 现在有一条微博,每个人要么点赞,要么送一个蜡烛 初始一些人利用bug反转了某些人的操作(赞变蜡烛 或者 蜡烛变成赞) 每当一个人被被反转,那么他的子树跟着反转,即一次反转一棵子树 现在你是管理员,你可以反转这些人的操作,反转次数任意次, 每次反转的代价分两种情况,如果这个人初始通过bug被反转过,代价是Y,否则是X 现在问你作为管理员,如何反转,使得 点赞的人价值总和 - 送蜡烛的人价值总和  最大 输入: 先…

本文出自   http://blog.csdn.net/shuangde800 题目链接:   hdu-3586 题意 给一棵n个节点的树,节点编号为1-n,根节点为1.每条边有权值,砍掉一条边要花费cost(w)    要砍掉一些边, 使得每个叶子节点无法走到根节点.    要求砍掉花费总和不能超过m的情况下,让每条边花费上限尽量低 思路 二分可以砍的边的权值上限,然后树形dp    f[i]: 表示让i子树所有的叶子节点无法到达i点的最小花费    f[i] = sum { min(w(i,…

Problem Description While studying the history of royal families, you want to know how wealthy each family is. While you have various 'net worth' figures for each individual throughout history, this is complicated by double counting caused by inherit…