hdu 1874 畅通工程续

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 using namespace std;
 5 
 6 int main ()
 7 {
 8     int a,b,c,n,m,l,k;
 9     const int INF=10000;
10     int map[205][205],r[205];
11     int vis[205];
12     while (cin>>n>>m)
13     {
14         memset(vis,0,sizeof(vis));
15         for (int i=0; i<n; i++)
16             for (int j=0; j<n; j++)
17             {
18                 if (i!=j)
19                 map[i][j]=INF;
20                 else
21                 map[i][j]=0;
22             }
23         while (m--)
24         {
25             cin>>a>>b>>c;
26             if (map[a][b]>c)
27             map[a][b]=map[b][a]=c;
28         }
29         cin>>a>>b;
30         for (int i=0; i<n; i++)
31         {
32             r[i]=map[a][i];
33             vis[i]=0;
34         }
35         for (int i=1; i<n; i++)
36         {
37             l=INF;
38             k=0;
39             for (int j=0; j<n; j++)
40             {
41                 if (vis[j]==0&&r[j]<l)
42                 {
43                     l=r[j];
44                     k=j;
45                 }
46             }
47             vis[k]=1;
48             for (int j=0; j<n; j++)
49             {
50                 if (!vis[j]&&r[j]>r[k]+map[k][j])
51                     r[j]=r[k]+map[k][j];
52             }
53 
54         }
55         //cin>>a>>b;
56         if (r[b]<INF)
57             printf ("%d\n",r[b]);
58         else
59             printf ("-1\n");
60     }
61     return 0;
62 }

 1 #include <cstdio>
 2 #include <cstring>
 3 using namespace std;
 4 #define INF 10000
 5 const int maxn = 201;
 6 int r[maxn][maxn];
 7 
 8 int main ()
 9 {
10     int n,m;
11     while (scanf("%d%d",&n,&m)!=EOF)
12     {
13         memset(r,INF,sizeof(r));
14         int a,b,c;
15         while (m--)
16         {
17             scanf("%d%d%d",&a,&b,&c);
18             if (r[a][b]>c)
19             {
20                 r[a][b]=r[b][a]=c;
21             }
22         }
23         for (int i=0; i<n; i++)
24             r[i][i]=0;
25         for (int k=0; k<n; k++)
26             for (int i=0; i<n; i++)
27                 for (int j=0; j<n; j++)
28                 {
29                     if (r[i][j]>r[i][k]+r[k][j])
30                     {
31                         r[i][j]=r[j][i]=r[i][k]+r[k][j];
32                     }
33                 }
34         scanf("%d%d",&a,&b);
35         if (r[a][b]<INF)
36             printf ("%d\n",r[a][b]);
37         else
38             printf ("-1\n");
39     }
40     return 0;
41 }