题目链接:http://poj.org/problem?id=1651 Description The multiplication puzzle is played with a row of cards, each containing a single positive integer. During the move player takes one card out of the row and scores the number of points equal to the prod…

题目链接:id=1651">点击打开链 题意: 给定一个数组,每次能够选择内部的一个数 i 消除,获得的价值就是 a[i-1] * a[i] * a[i+1] 问最小价值 思路: dp[l,r] = min( dp[l, i] + dp[i, r] + a[l] * a[i] * a[r]); #include <cstdio> #include <iostream> #include <algorithm> #include <queue>…

传送门:http://poj.org/problem?id=1651 Multiplication Puzzle Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 13109   Accepted: 8034 Description The multiplication puzzle is played with a row of cards, each containing a single positive intege…

题意: 给出一个序列,共n个正整数,要求将区间[2,n-1]全部删去,只剩下a[1]和a[n],也就是一共需要删除n-2个数字,但是每次只能删除一个数字,且会获得该数字与其旁边两个数字的积的分数,问最少可以获得多少分数? 思路: 类似于矩阵连乘的问题,用区间DP来做. 假设已知区间[i,k-1]和[k+1,j]各自完成删除所获得的最少分数,那么a[k]是区间a[i,j]内唯一剩下的一个数,那么删除该数字就会获得a[k]*a[i-1]*a[i+1]的分数了.在枚举k的时候要保证[i,j]的任一子区…

Description The multiplication puzzle is played with a row of cards, each containing a single positive integer. During the move player takes one card out of the row and scores the number of points equal to the product of the number on the card taken…

Multiplication Puzzle Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 10010   Accepted: 6188 Description The multiplication puzzle is played with a row of cards, each containing a single positive integer. During the move player takes one…

Description The multiplication puzzle is played with a row of cards, each containing a single positive integer. During the move player takes one card out of the row and scores the number of points equal to the product of the number on the card taken…

<题目链接> 题目大意: 一个由小写字母组成的字符串,给出字符的种类,以及字符串的长度,再给出添加每个字符和删除每个字符的代价,问你要使这个字符串变成回文串的最小代价. 解题分析: 一道区间DP的好题.因为本题字符串的长度最大为2e3,所以考虑$O(n^2)$直接枚举区间的两个端点,然后对枚举的区间进行状态转移,大体上有三种转移情况: $dp[l][r]$表示$[l,r]$为回文串的最小代价 对于区间$[l,r]$,当$str[l]==str[r]$时,$dp[l][r]=dp[l+1][r-…

题意 : 给出一个由 n 中字母组成的长度为 m 的串,给出 n 种字母添加和删除花费的代价,求让给出的串变成回文串的代价. 分析 :  原始模型 ==> 题意和本题差不多,有添和删但是并无代价之分,要求最少操作几次才能是其变成回文串 ① 其实细想之后就会发现如果没有代价之分的话删除和增添其实是一样的,那么除了原串原本拥有的最长回文串不用进行考虑处理,其他都需要进行删除或者增添来使得原串变成回文串,所以只要对原串 S 和其反向串 S' 找出两者的最长公共子串长度 L 再用总长减去 L 即可 ②…

题目链接:http://poj.org/problem? id=1651 题意:初使ans=0,每次消去一个值,位置在pos(pos!=1 && pos !=n) 同一时候ans+=a[pos-1]*a[pos]*a[pos+1].一直消元素直到最后剩余2个,求方案最小的ans是多少? 代码: #include <stdio.h> #include <ctime> #include <math.h> #include <limits.h> #…