poj3186（区间DP）

poj3186(区间dp)

题目链接:http://poj.org/problem?id=3186 题意:给一行n个数,每次可以取出行首或者行末的数,如果第ai是第i次取出的,可以得到ai*i的收益,求最大的总收益: 思路:区间dp 我们可以用dp[i][j]表示当前是取出第i个行首元素,第j次取出行尾元素,那么不然想到动态转移方程式: dp[i][j]=max(dp[i-1][j]+a[i]*(i+j), dp[i][j-1]+a[n-j+1]*(i+j)) 注意一下边界情况就ok啦... 代码: #include <i…

【POJ - 3186】Treats for the Cows （区间dp）

Treats for the Cows 先搬中文 Descriptions: 给你n个数字v(1),v(2),...,v(n-1),v(n),每次你可以取出最左端的数字或者取出最右端的数字,一共取n次取完.假设你第i次取的数字是x,你可以获得i*x的价值.你需要规划取数顺序,使获得的总价值之和最大. Input 第一行一个数字n(1<=n<=2000). 下面n行每行一个数字v(i).(1<=v(i)<=1000) Output 输出一个数字,表示最大总价值和. Sample In…

题目链接:http://poj.org/problem?id=3186 思路: 区间DP,给treat编号为1..n,状态很明显是上界i和下界j,dp[i][j]表示从下标i到下标j之间数据的最大价值.可以正向转移,从dp[1][0]开始,也可以逆向转移,从dp[i][i]开始.我这里是正向转移,状态转移方程如下: if(i>1&&j<n) dp[i][j]=max(dp[i-1][j]+(n-1-(j-i))*a[i-1],dp[i][j+1]+…

kuangbin专题十二 POJ3186 Treats for the Cows （区间dp）

Treats for the Cows Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 7949 Accepted: 4217 Description FJ has purchased N (1 <= N <= 2000) yummy treats for the cows who get money for giving vast amounts of milk. FJ sells one treat per da…

luogu2858奶牛零食题解--区间DP

题目链接 https://www.luogu.org/problemnew/show/P2858 一句话题意: https://cn.vjudge.net/problem/POJ-3186#author=Re0 分析很显然这道题是不行滴,但是把这个数列看作从一个个区间倒着向外扩展取数而成的话,这样就保证了最优子结构和无后效性两个特点,于是就开始DP了按照区间DP一贯的套路,先初始化元区间,也就是长度为1的区间值\(f[i][i]=a[i] * n\),为什么要倒着取呢?前面已经说明了,这样保…

【BZOJ-4380】Myjnie 区间DP

4380: [POI2015]Myjnie Time Limit: 40 Sec Memory Limit: 256 MBSec Special JudgeSubmit: 162 Solved: 82[Submit][Status][Discuss] Description 有n家洗车店从左往右排成一排,每家店都有一个正整数价格p[i].有m个人要来消费,第i个人会驶过第a[i]个开始一直到第b[i]个洗车店,且会选择这些店中最便宜的一个进行一次消费.但是如果这个最便宜的价格大于c[i],…

【POJ-1390】Blocks 区间DP

Blocks Time Limit: 5000MS Memory Limit: 65536K Total Submissions: 5252 Accepted: 2165 Description Some of you may have played a game called 'Blocks'. There are n blocks in a row, each box has a color. Here is an example: Gold, Silver, Silver, Sil…

区间DP LightOJ 1422 Halloween Costumes

http://lightoj.com/volume_showproblem.php?problem=1422 做的第一道区间DP的题目,试水. 参考解题报告: http://www.cnblogs.com/ziyi--caolu/p/3236035.html http://blog.csdn.net/hcbbt/article/details/15478095 dp[i][j]为第i天到第j天要穿的最少衣服,考虑第i天,如果后面的[i+1, j]天的衣服不要管,那么dp[i][j] = dp[i…

BZOJ1055: [HAOI2008]玩具取名[区间DP]

1055: [HAOI2008]玩具取名 Time Limit: 10 Sec Memory Limit: 162 MBSubmit: 1588 Solved: 925[Submit][Status][Discuss] Description 某人有一套玩具,并想法给玩具命名.首先他选择WING四个字母中的任意一个字母作为玩具的基本名字.然后他会根据自己的喜好,将名字中任意一个字母用“WING”中任意两个字母代替,使得自己的名字能够扩充得很长. 现在,他想请你猜猜某一个很长的名字,最初可能…

poj2955 Brackets (区间dp)

题目链接:http://poj.org/problem?id=2955 题意:给定字符串求括号匹配最多时的子串长度. 区间dp,状态转移方程: dp[i][j]=max ( dp[i][j] , 2+dp[i+1][k-1]+dp[k+1][j] ); 代码: #include<iostream> #include<cstdio> #include<algorithm> #include<cstring> using namespace std; #def…

HDU5900 QSC and Master（区间DP + 最小费用最大流）

题目 Source http://acm.hdu.edu.cn/showproblem.php?pid=5900 Description Every school has some legends, Northeastern University is the same. Enter from the north gate of Northeastern University,You are facing the main building of Northeastern University.…

BZOJ 1260&UVa 4394 区间DP

题意: 给一段字符串成段染色,问染成目标串最少次数. SOL: 区间DP... DP[i][j]表示从i染到j最小代价转移:dp[i][j]=min(dp[i][j],dp[i+1][k]+dp[k+1][j]); CODE: BZ: /*================================================================= # Created time: 2016-03-28 21:10 # Filename: uva4394.cpp # Desc…

区间dp总结篇

前言:这两天没有写什么题目,把前两周做的有些意思的背包题和最长递增.公共子序列写了个总结.反过去写总结,总能让自己有一番收获......就区间dp来说,一开始我完全不明白它是怎么应用的,甚至于看解题报告都看不明白,而到了现在,遇到区间dp之类的题目,我不至于没有任何方向,慢慢的推导,有些题目没有自己想象的那么难,还是可以推导出转移方程的,有些题目,在自己推导过后,与解题报告相对照,也总能有一番全新的收获.我是觉得,解题报告需要看,但是怎么看,如何看,却是值得思量....... 1.Light o…

Uva 10891 经典博弈区间DP

经典博弈区间DP 题目链接:https://uva.onlinejudge.org/external/108/p10891.pdf 题意: 给定n个数字,A和B可以从这串数字的两端任意选数字,一次只能从一端选取. 并且A B都尽力使自己选择的结果为最大的,可以理解成A B每一步走的都是最优的. 如果A先选择,则A B差值最大是多少. 分析: 总和是一定的,所以一个得分越高,另一个人的得分越低.当前状态总是最开始的状态的一个子状态. d(i,j): 先手取 i ~ j 最优策略下,得分最大值. d…

2016 年沈阳网络赛---QSC and Master(区间DP)

题目链接 http://acm.hdu.edu.cn/showproblem.php?pid=5900 Problem Description Every school has some legends, Northeastern University is the same. Enter from the north gate of Northeastern University,You are facing the main building of Northeastern Universi…

UVALive 4987---Evacuation Plan（区间DP）

题目链接 https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=2988 problem Description Flatland government is building a new highway that will be used to transport weapons from its main weapon plan…

HDU 4283---You Are the One（区间DP）

题目链接 http://acm.split.hdu.edu.cn/showproblem.php?pid=4283 Problem Description The TV shows such as You Are the One has been very popular. In order to meet the need of boys who are still single, TJUT hold the show itself. The show is hold in the Small…

HDU 4293---Groups(区间DP)

题目链接 http://acm.split.hdu.edu.cn/showproblem.php?pid=4293 Problem Description After the regional contest, all the ACMers are walking alone a very long avenue to the dining hall in groups. Groups can vary in size for kinds of reasons, which means, sev…

HDU 1141---Brackets Sequence（区间DP）

题目链接 http://poj.org/problem?id=1141 Description Let us define a regular brackets sequence in the following way: 1. Empty sequence is a regular sequence. 2. If S is a regular sequence, then (S) and [S] are both regular sequences. 3. If A and B are reg…

Light OJ 1031---Easy Game(区间DP)

题目链接 http://lightoj.com/volume_showproblem.php?problem=1031 Description You are playing a two player game. Initially there are n integer numbers in an array and player A and B get chance to take them alternatively. Each player can take one or more nu…