HDU 3665 Seaside(Dijkstra)

题目链接

区域赛的水题。。。题意理解好了就OK了，模版题，还是调试了一会，自己对代码不太熟练啊。

 1 #include <stdio.h>
 2 #include <string.h>
 3 #define N 1000000
 4 int main()
 5 {
 6     int p[20][20],low[13],o[13],sea[13];
 7     int i,j,k,n,a,b,w,ev,min;
 8     while(scanf("%d",&n)!=EOF)
 9     {
10         memset(o,0,sizeof(o));
11         memset(sea,0,sizeof(sea));
12         for(i = 0;i <= n-1;i ++)
13         for(j = 0;j <= n-1;j ++)
14         {
15             if(i!=j)
16             p[i][j] = N;
17             else
18             p[i][j] = 0;
19         }
20         for(i = 0;i <= n-1;i ++)
21         {
22             scanf("%d%d",&a,&b);
23             if(b == 1) sea[i] = 1;
24             for(j = 1;j <= a;j ++)
25             {
26                 scanf("%d%d",&ev,&w);
27                 if(p[i][ev] > w)
28                 p[i][ev] = w;
29                 if(p[ev][i] > w)
30                 p[ev][i] = w;
31             }
32         }
33         for(i = 0;i <= n-1;i ++)
34         {
35             low[i] = p[0][i];
36         }
37         o[0] = 1;
38         for(i = 1;i <= n-2;i ++)
39         {
40             min = N;
41             for(j = 0;j <= n-1;j ++)
42             {
43                 if(min > low[j]&&o[j] == 0)
44                 {
45                     min = low[j];
46                     k = j;
47                 }
48             }
49             o[k] = 1;
50             for(j = 0;j <= n-1;j ++)
51             {
52                 if(o[j] == 0&&low[j] > min + p[k][j])
53                 {
54                     low[j] = p[k][j]+min;
55                 }
56             }
57         }
58         min = N;
59         for(i = 0;i <= n-1;i ++)
60         {
61             if(min > low[i]&&sea[i])
62             {
63                 min = low[i];
64             }
65         }
66         printf("%d\n",min);
67     }
68     return 0;
69 }
posted @ 2012-06-15 10:21  Naix_x  阅读(181)  评论(0)  编辑  收藏  举报