ICode9

精准搜索请尝试: 精确搜索
首页 > 其他分享> 文章详细

hdu 三部曲 Cheapest Palindrome

2019-06-26 12:49:02  阅读:236  来源: 互联网

标签:hdu Palindrome string Cheapest int cost include ID dp


Problem Description

Keeping track of all the cows can be a tricky task so Farmer John has installed a system to automate it. He has installed on each cow an electronic ID tag that the system will read as the cows pass by a scanner. Each ID tag's contents are currently a single string with length M (1 ≤ M ≤ 2,000) characters drawn from an alphabet of N (1 ≤ N ≤ 26) different symbols (namely, the lower-case roman alphabet).

Cows, being the mischievous creatures they are, sometimes try to spoof the system by walking backwards. While a cow whose ID is "abcba" would read the same no matter which direction the she walks, a cow with the ID "abcb" can potentially register as two different IDs ("abcb" and "bcba").

FJ would like to change the cows's ID tags so they read the same no matter which direction the cow walks by. For example, "abcb" can be changed by adding "a" at the end to form "abcba" so that the ID is palindromic (reads the same forwards and backwards). Some other ways to change the ID to be palindromic are include adding the three letters "bcb" to the begining to yield the ID "bcbabcb" or removing the letter "a" to yield the ID "bcb". One can add or remove characters at any location in the string yielding a string longer or shorter than the original string.

Unfortunately as the ID tags are electronic, each character insertion or deletion has a cost (0 ≤ cost ≤ 10,000) which varies depending on exactly which character value to be added or deleted. Given the content of a cow's ID tag and the cost of inserting or deleting each of the alphabet's characters, find the minimum cost to change the ID tag so it satisfies FJ's requirements. An empty ID tag is considered to satisfy the requirements of reading the same forward and backward. Only letters with associated costs can be added to a string.

  Input Line 1: Two space-separated integers: N and M Line 2: This line contains exactly M characters which constitute the initial ID string Lines 3..N+2: Each line contains three space-separated entities: a character of the input alphabet and two integers which are respectively the cost of adding and deleting that character.   Output Line 1: A single line with a single integer that is the minimum cost to change the given name tag.   Sample Input 3 4 abcb a 1000 1100 b 350 700 c 200 800   Sample Output 900 ********************************************************************************************* 球带权的回文串 *********************************************************************************************
 1 /*
 2 求有权值的回文串,
 3 先预处理,求出费用的最小值,
 4 再按一般方法求出最小费用
 5 */
 6 #include<iostream>
 7 #include<string>
 8 #include<cstring>
 9 #include<queue>
10 #include<cstdio>
11 using namespace std;
12 int dp[2011][2011];
13 int n,m,i,j,k,x,y;
14 string  str1;
15 char  ch;
16 int cost[1001];
17 int min(int a,int b)
18 {
19     return a>b?b:a;
20 }
21 int main()
22 {
23     cin>>n>>m;
24     cin>>str1;
25     getchar();
26     memset(dp,0,sizeof(dp));
27     for(i=0;i<n;i++)
28     {
29         ch=getchar();
30         //cout<<ch<<endl;
31         getchar();
32         cin>>x>>y;
33         cost[ch-'a']=min(x,y);
34         getchar();
35     }
36     for(i=1;i<m;i++)
37      for(j=i-1;j>=0;j--)
38       {
39           dp[j][i]=min(dp[j+1][i]+cost[str1[j]-'a'],dp[j][i-1]+cost[str1[i]-'a']);
40            if(str1[i]==str1[j])
41             dp[j][i]=min(dp[j][i],dp[j+1][i-1]);
42       }
43       cout<<dp[0][m-1]<<endl;
44       return 0;
45 }
View Code

坚持!!!

转载于:https://www.cnblogs.com/sdau--codeants/p/3329569.html

标签:hdu,Palindrome,string,Cheapest,int,cost,include,ID,dp
来源: https://blog.csdn.net/weixin_34261739/article/details/93727629

本站声明: 1. iCode9 技术分享网(下文简称本站)提供的所有内容,仅供技术学习、探讨和分享;
2. 关于本站的所有留言、评论、转载及引用,纯属内容发起人的个人观点,与本站观点和立场无关;
3. 关于本站的所有言论和文字,纯属内容发起人的个人观点,与本站观点和立场无关;
4. 本站文章均是网友提供,不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属;如您发现该文章侵犯了您的权益,可联系我们第一时间进行删除;
5. 本站为非盈利性的个人网站,所有内容不会用来进行牟利,也不会利用任何形式的广告来间接获益,纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。

专注分享技术,共同学习,共同进步。侵权联系[81616952@qq.com]

Copyright (C)ICode9.com, All Rights Reserved.

ICode9版权所有