Jungle Roads

The Head Elder of the tropical island of Lagrishan has a problem. A burst of foreign aid money was spent on extra roads between villages some years ago. But the jungle overtakes roads relentlessly, so the large road network is too expensive to maintain. The Council of Elders must choose to stop maintaining some roads. The map above on the left shows all the roads in use now and the cost in aacms per month to maintain them. Of course there needs to be some way to get between all the villages on maintained roads, even if the route is not as short as before. The Chief Elder would like to tell the Council of Elders what would be the smallest amount they could spend in aacms per month to maintain roads that would connect all the villages. The villages are labeled A through I in the maps above. The map on the right shows the roads that could be maintained most cheaply, for 216 aacms per month. Your task is to write a program that will solve such problems.

Input

The input consists of one to 100 data sets, followed by a final line containing only 0. Each data set starts with a line containing only a number n, which is the number of villages, 1 < n < 27, and the villages are labeled with the first n letters of the alphabet, capitalized. Each data set is completed with n-1 lines that start with village labels in alphabetical order. There is no line for the last village. Each line for a village starts with the village label followed by a number, k, of roads from this village to villages with labels later in the alphabet. If k is greater than 0, the line continues with data for each of the k roads. The data for each road is the village label for the other end of the road followed by the monthly maintenance cost in aacms for the road. Maintenance costs will be positive integers less than 100. All data fields in the row are separated by single blanks. The road network will always allow travel between all the villages. The network will never have more than 75 roads. No village will have more than 15 roads going to other villages (before or after in the alphabet). In the sample input below, the first data set goes with the map above.

Output

The output is one integer per line for each data set: the minimum cost in aacms per month to maintain a road system that connect all the villages. Caution: A brute force solution that examines every possible set of roads will not finish within the one minute time limit.

Sample Input

9

A 2 B 12 I 25

B 3 C 10 H 40 I 8

C 2 D 18 G 55

D 1 E 44

E 2 F 60 G 38

F 0

G 1 H 35

H 1 I 35

3

A 2 B 10 C 40

B 1 C 20

0

Sample Output

216

30

题解:最小生成树

(水题)

注意poj上用scanf()和printf()可能运行错误,

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<iostream>
using namespace std;
struct node{
int x,y;
int price;
}a[1000]; int vis[100]; int find(int x)
{
if(vis[x]==x)
return x;
return vis[x]=find(vis[x]);
} bool cmp(node a,node b)
{
return a.price <b.price ;
} void join(int a,int b)
{
int x=find(a);
int y=find(b);
if(x!=y)
vis[x]=y;
} int main()
{
int n;
char str[200];
memset(str,0,sizeof(str));
int zzz=1;
for(int i='A';i<='Z';i++)
str[i]=zzz++;
while(cin>>n&&n)
{ for(int i=1;i<=n;i++)
vis[i]=i; int j=0;
for(int i=0;i<n-1;i++)
{
char c;
getchar();
cin>>c;
int m;
// scanf("%d",&m);
cin>>m;
while(m--)
{
char s;
getchar();
// scanf("%c",&s);
cin>>s;
int u;
//scanf("%d",&u);
cin>>u;
a[j].x =str[c];
a[j].y =str[s];
a[j++].price =u;
}
} sort(a,a+j,cmp);
int sum=0;
for(int i=0;i<j;i++)
{
if(find(a[i].x )!=find(a[i].y ))
sum+=a[i].price ;
join(a[i].x ,a[i].y );
}
// printf("%d\n",sum);
cout<<sum<<endl; }
return 0;
}

HDU1301 Jungle Roads的更多相关文章

  1. HDU-1301 Jungle Roads(最小生成树[Prim])

    Jungle Roads Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 65536/32768K (Java/Other) Total ...

  2. hdu1301 Jungle Roads 最小生成树

    The Head Elder of the tropical island of Lagrishan has a problem. A burst of foreign aid money was s ...

  3. HDU1301 Jungle Roads(Kruskal)

    Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission( ...

  4. hdu1301 Jungle Roads (Prim)

    题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1301 依旧Prim............不多说了 #include<iostream> ...

  5. hdu1301 Jungle Roads 基础最小生成树

    #include<iostream> #include<algorithm> using namespace std; ; int n, m; ]; struct node { ...

  6. Jungle Roads[HDU1301]

    Jungle Roads Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Tota ...

  7. HDU1301&&POJ1251 Jungle Roads 2017-04-12 23:27 40人阅读 评论(0) 收藏

    Jungle Roads Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 25993   Accepted: 12181 De ...

  8. poj 1251 Jungle Roads (最小生成树)

    poj   1251  Jungle Roads  (最小生成树) Link: http://poj.org/problem?id=1251 Jungle Roads Time Limit: 1000 ...

  9. POJ 1251 Jungle Roads (prim)

    D - Jungle Roads Time Limit:1000MS     Memory Limit:10000KB     64bit IO Format:%I64d & %I64u Su ...

随机推荐

  1. Git常用操作命令收集

      Git常用操作命令收集 1.进入本地仓库访问位置之后执行命令 1) 远程仓库相关命令 检出仓库:$ git clone git://github.com/jquery/jquery.git 查看远 ...

  2. 《C#高效编程》读书笔记07-理解GetHashCode()的陷阱

    GetHashCode()函数仅会在一个地方用到,即为基于散列(hash)的集合定义的散列键时,此类集合包括HashSet和Dictionary<K,V>容器等. 但object基类提供的 ...

  3. 检查python以及django是否安装配置成功

    首先说明下,我使用pycharm作为开发的IDE,在第一次创建django项目的时候,会自动安装django包的.(网上也有很多单独安装的方法),环境变量配置成功后,就是用下面的方法检测安装成功与否. ...

  4. Error: connect ECONNREFUSED 127.0.0.1:8080

    Error: connect ECONNREFUSED 127.0.0.1:8080    at Object.exports._errnoException (util.js:1018:11)    ...

  5. 浅谈WebService的调用

    0.前言 前段时间,公司和电信有个合作,产品对接电信的某个平台,使用了WebService接口的调用,实现了业务受理以及单点登录.终于使用到了WebService,楼主还是比较兴奋的,目前功能已经上线 ...

  6. OSS基本概念介绍

    存储空间(Bucket): 存储空间是用于存储对象(Object)的容器,所有的对象都必须隶属于某个存储空间. 可以设置和修改存储空间属性用来控制地域.访问权限.生命周期等,这些属性设置直接作用于该存 ...

  7. bt5 r3下metasploit连接postgresql数据库

    一.查看PostgreSQL使用的端口,默认为7337 #: netstat -tnpl |grep postgres 二.查看Msf配置,里面有默认的用户名和密码 默认配置文件:/opt/metas ...

  8. 真正理解 git fetch, git pull 以及 FETCH_HEAD(转)

    转自http://www.cnblogs.com/ToDoToTry/p/4095626.html 真正理解 git fetch, git pull 要讲清楚git fetch,git pull,必须 ...

  9. StackOverflow之旅<2>------{HashMap和Hashtable的区别}

    问题 在Java中HashMap和Hashtable的区别? 哪一个对于多线程应用程序更好? 回答 Hashtable是同步的,加了synchronized锁,而HashMap不是.没有加synchr ...

  10. Aizu 2301 Sleeping Time(概率,剪枝)

    根据概率公式dfs即可,判断和区间[T-E,T+E]是否有交,控制层数. #include<bits/stdc++.h> using namespace std; int K,R,L; d ...