ZOJ 3166题解 最短路径之Floyd算法

 1 #include<stdio.h>
 2 #include<stdlib.h>
 3 #include<string.h>
 4 #define Maxint 9999999
 5 #define Max 101
 6 
 7 int main()
 8 {
 9     int M, N, hotel[101], a, C, b, t;
10     int i, j, k, r, sum, dist[101][101];
11 
12    while (scanf("%d%d",&N, &C) != EOF)
13    {
14       for (i=1; i<=N; i++)
15        for (j=1; j<=N; j++)
16        {
17          dist[i][j] = Maxint; 
18        } 
19       sum = Maxint;  
20       for (i=1; i<=C; i++)
21       {
22         scanf("%d",&hotel[i]);
23       }  
24       scanf("%d", &M); 
25       for(i=0; i<M; i++)
26       {
27         scanf("%d%d%d", &a, &b, &t);       
28         dist[a][b] = t;
29       }
30      for (k=1; k<=N; k++)
31      {
32        for (i=1; i<=N; i++)
33         for (j=1; j<=N; j++)
34         {
35           if(dist[i][j] > dist[i][k]+dist[k][j]) 
36              dist[i][j] = dist[i][k] + dist[k][j];           
37         }
38      }                      
39       r = 0;
40       for (i=1; i<=C; i++)
41       {
42          if (dist[hotel[i]][hotel[i]] < sum)
43          {
44            sum = dist[hotel[i]][hotel[i]];
45            r = hotel[i];
46          }
47       }
48       if( r )
49         printf("%d\n",r);
50       else
51         printf("I will nerver go to that city!\n");
52     }
53    return 0;
54 }
55