题目链接:http://poj.org/problem?id=3186 题目大意:给出的一系列的数字,可以看成一个双向队列,每次只能从队首或者队尾出队,第n个出队就拿这个数乘以n,最后将和加起来,求最大和. 解题思路:有两种写法: ①这是我一开始想的,从外推到内,设立数组dp[i][j]表示剩下i~j时的最优解,则有状态转移方程: dp[i][j]=dp[i][j]=max(dp[i-1][j]+a[i-1]*(n-(j-i+1)),dp[i][j+1]+a[j+1]*(n-(j+1-i)))…

详见代码 #include <stdio.h> #include <algorithm> #include <string.h> using namespace std; ]; ][];//i到j的最大和是多少 int main() { // freopen("in.txt","r",stdin); int t; while(~scanf("%d",&t)) { ; i<=t; i++) { sc…

题目链接  Treats for the Cows 直接区间DP就好了,用记忆化搜索是很方便的. #include <cstdio> #include <cstring> #include <iostream> #include <algorithm> using namespace std; #define rep(i,a,b) for(int i(a); i <= (b); ++i) #define LL long long + ; LL f[Q]…

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 day and wants to maximize the money he receives over a given period time. The treats are interesting for many reasons…

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 day and wants to maximize the money he receives over a given period time. The treats are interesting for…

题目来源:http://poj.org/problem?id=3186 (http://www.fjutacm.com/Problem.jsp?pid=1389) /** 题目意思: 约翰经常给产奶量高的奶牛发特殊津贴,于是很快奶牛们拥有了大笔不知该怎么花的钱． 为此,约翰购置了N(1≤N≤2000)份美味的零食来卖给奶牛们．每天约翰售出一份零食． 当然约翰希望这些零食全部售出后能得到最大的收益．这些零食有以下这些有趣的特性: 零食按照1．．N编号,它们被排成一列放在一个很长的盒子里．盒子的两端…

题意:给一个数组v,每次可以取前面的或者后面的,第k次取的v[i]价值为v[i]*k,问总价值最大是多少. 区间dp. 区间dp可以不枚举len  直接枚举i和j即可  见代码 #include <iostream> #include <cstdio> #include <algorithm> #include <cstring> using namespace std; #define maxx 2010 int dp[maxx][maxx]; int m…

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 day and wants to maximize the money he receives over a given period time. The treats are interesting for…

[BZOJ 1652][USACO 06FEB]Treats for the Cows 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 day and wants to maximize the money he receives over a given…

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…