POJ_3186_Treats for the Cows
Time Limit: 1000MS | Memory Limit: 65536K | |
Total Submissions: 6568 | Accepted: 3459 |
Description
The treats are interesting for many reasons:
- The treats are numbered 1..N and stored sequentially in single file in a long box that is open at both ends. On any day, FJ can retrieve one treat from either end of his stash of treats.
- Like fine wines and delicious cheeses, the treats improve with age and command greater prices.
- The treats are not uniform: some are better and have higher intrinsic value. Treat i has value v(i) (1 <= v(i) <= 1000).
- Cows pay more for treats that have aged longer: a cow will pay v(i)*a for a treat of age a.
Given the values v(i) of each of the treats lined up in order of the index i in their box, what is the greatest value FJ can receive for them if he orders their sale optimally?
The first treat is sold on day 1 and has age a=1. Each subsequent day increases the age by 1.
Input
Lines 2..N+1: Line i+1 contains the value of treat v(i)
Output
Sample Input
5
1
3
1
5
2
Sample Output
43
Hint
Five treats. On the first day FJ can sell either treat #1 (value 1) or treat #5 (value 2).
FJ sells the treats (values 1, 3, 1, 5, 2) in the following order of indices: 1, 5, 2, 3, 4, making 1x1 + 2x2 + 3x3 + 4x1 + 5x5 = 43.
Source
- 最开始想的是贪心
- 每次取两端最小的,这样把大的留在最后,总和最大
- 但是WA
- 原因在于贪心的局限性上,我们不能保证这样的贪心策略在应对诸如当前右端比左端大但是右端第二个数比两端点都小的情况下怎样取舍的情形下怎样做
- 所以还是应该dp
- 不难看出每一个点在双端队列中的出队顺序排除开始的两端是1到n,其他的都是2到n,所以我们在确定一定区间的最优值之后可以向两边递推
#include <iostream>
#include <string>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <climits>
#include <cmath>
#include <vector>
#include <queue>
#include <stack>
#include <set>
#include <map>
using namespace std;
typedef long long LL ;
typedef unsigned long long ULL ;
const int maxn = 2e3 + ;
const int inf = 0x3f3f3f3f ;
const int npos = - ;
const int mod = 1e9 + ;
const int mxx = + ;
const double eps = 1e- ;
const double PI = acos(-1.0) ; int dp[maxn][maxn], a[maxn], n;
int main(){
// freopen("in.txt","r",stdin);
// freopen("out.txt","w",stdout);
while(~scanf("%d",&n)){
for(int i=;i<=n;i++){
scanf("%d",&a[i]);
dp[i][]=a[i]*n;
}
for(int j=;j<n;j++)
for(int i=n-j;i>;i--)
dp[i][j]=max(dp[i][j-]+a[i+j]*(n-j),dp[i+][j-]+a[i]*(n-j));
printf("%d\n",dp[][n-]);
}
return ;
}
POJ_3186_Treats for the Cows的更多相关文章
- [LeetCode] Bulls and Cows 公母牛游戏
You are playing the following Bulls and Cows game with your friend: You write a 4-digit secret numbe ...
- POJ 2186 Popular Cows(Targin缩点)
传送门 Popular Cows Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 31808 Accepted: 1292 ...
- POJ 2387 Til the Cows Come Home(最短路 Dijkstra/spfa)
传送门 Til the Cows Come Home Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 46727 Acce ...
- LeetCode 299 Bulls and Cows
Problem: You are playing the following Bulls and Cows game with your friend: You write down a number ...
- [Leetcode] Bulls and Cows
You are playing the following Bulls and Cows game with your friend: You write a 4-digit secret numbe ...
- 【BZOJ3314】 [Usaco2013 Nov]Crowded Cows 单调队列
第一次写单调队列太垃圾... 左右各扫一遍即可. #include <iostream> #include <cstdio> #include <cstring> ...
- POJ2186 Popular Cows [强连通分量|缩点]
Popular Cows Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 31241 Accepted: 12691 De ...
- Poj2186Popular Cows
Popular Cows Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 31533 Accepted: 12817 De ...
- [poj2182] Lost Cows (线段树)
线段树 Description N (2 <= N <= 8,000) cows have unique brands in the range 1..N. In a spectacula ...
随机推荐
- ios开发之--比较两个数组里面的值是否相同
比较两个数组里面的内容是否相同,代码如下: NSArray *array1 = [NSArray arrayWithObjects:@"a", @"b", @& ...
- iptables相关操作以及简单理解端口和服务之间关系
一般CentOS7默认安装的是firewall不是iptables 1.查看firewall状态 firewall-cmd --state 关闭后显示not running,开启后显示running ...
- 【Ubuntu】Windows 远程桌面连接ubuntu及xrdp的一些小问题(远程桌面闪退、连接失败、tab补全功能,无菜单栏,error - problem connecting )【转】
转:https://blog.csdn.net/u014447845/article/details/80291678 1.远程桌面闪退,shell可以用的问题:(1)需要在该用户目录创建一个.xse ...
- Data Guard 主备库角色转换
1. switchover操作 1.1 备库先关闭实时日志应用 standby>alter database recover managed standby database cancel; 1 ...
- linux-友好显示文件大小
4850905319b / 1024 /1024/1024 = 4.6G ls -lh
- SpringBoot(五)-- 整合Spring的拦截器
一.步骤 1.创建我们自己的拦截器类并实现 HandlerInterceptor 接口. 2.创建一个Java类继承WebMvcConfigurerAdapter,并重写 addInterceptor ...
- SpringBoot(二)-- 支持JSP
SpringBoot虽然支持JSP,但是官方不推荐使用.看网上说,毕竟JSP是淘汰的技术了,泪奔,刚接触 就淘汰.. SpringBoot集成JSP的方法: 1.配置application.prope ...
- zabbix监控第一台服务器
客户机的IP是192.168.0.80,主机名是wls12c 1. 安装客户端, 1.1 新建zabbix的用户 groupadd zabbix useradd -g zabbix zabbix 1. ...
- code_blocks 使用操作手册
38 39 编译以上程序,产生如下提示信息. 如此简 ...
- gearman 简介
附件 Gearman.doc 1:介绍gearman 1.1 简介 Gearman是一个用来把工作委派给其他机器.分布式的调用更适合做某项工作的机器.并发的做某项工作在多个调用间做负载均衡.或用来在 ...