zoj 1406 Jungle Roads poj 1251

  1 #include <iostream>
  2 #include<stdio.h>
  3 #include<string.h>
  4 #include<algorithm>
  5 #define MAXN 30
  6 #define MAXM 1000
  7 using namespace std;
  8 
  9 struct edge
 10 {
 11     int u,v,w;
 12 }edges[MAXM];
 13 int parent[MAXN];
 14 int N,m;
 15 int i,j;
 16 int sumweight;
 17 void UFset()
 18 {
 19     for(i=1;i<=N;i++)
 20     {
 21         parent[i]=-1;
 22     }
 23 }
 24 int Find(int x)
 25 {
 26     int s;
 27     for(s=x;parent[s]>=0;s=parent[s]);
 28     while(s!=x)
 29     {
 30         int tmp=parent[x];
 31         parent[x]=s;
 32         x=tmp;
 33     }
 34     return s;
 35 }
 36 void Union (int R1,int R2)
 37 {
 38     int r1=Find(R1);
 39     int r2=Find(R2);
 40     int tmp=parent[r1]+parent[r2];
 41     if(r1<r2)
 42     {
 43         parent[r2]=r1;
 44         parent[r1]=tmp;
 45     }
 46     else
 47     {
 48         parent[r1]=r2;
 49         parent[r2]=tmp;
 50     }
 51 }
 52 int cmp(const void *a,const void *b)
 53 {
 54     edge aa=*(const edge *)a;
 55     edge bb=*(const edge *)b;
 56     if(aa.w>bb.w)
 57     return 1;
 58     else return -1;
 59 }
 60 void Kruskal()
 61 {
 62     int num=0;
 63     int u,v;
 64     UFset();
 65     for(i=0; i<m; i++)
 66     {
 67         u=edges[i].u;
 68         v=edges[i].v;
 69         if(Find(u)!=Find(v))
 70         {
 71             sumweight+=edges[i].w;
 72             num++;
 73             Union(u,v);
 74         }
 75         if(num>=N-1)
 76         break;
 77     }
 78 }
 79 int main()
 80 {
 81     while(1)
 82     {
 83         char c,cc;
 84         scanf("%d",&N);
 85         if(N==0)break;
 86         int mi=0;//±ßµÄÐòºÅ
 87         int numm;
 88         for(i=0; i<N-1; i++)
 89         {
 90             getchar();
 91             scanf("%c",&c);
 92             scanf("%d",&numm);
 93             for(j=0;j<numm;j++)
 94             {
 95                 getchar();
 96                 scanf("%c %d",&cc,&edges[mi].w);
 97                 edges[mi].u=c-'A'+1;
 98                 edges[mi].v=cc-'A'+1;
 99                 //printf("%d %d\n",edges[mi].u,edges[mi].v);
100                 mi++;
101             }
102         }
103         m=mi;
104         qsort(edges,m,sizeof(edges[0]),cmp);
105         sumweight=0;
106         Kruskal();
107         printf("%d\n",sumweight);
108     }
109     return 0;
110 }
View Code
posted on 2013-08-07 15:58 点A点C 阅读(141) 评论(0) 编辑收藏举报
刷新页面返回顶部
zoj 1406 Jungle Roads poj 1251

导航

公告
