HDU 1596 最短路变形

这道题怎么都是TLE，报警了，先放在这

http://acm.hdu.edu.cn/showproblem.php?pid=1596

 #include <iostream>
 #include <iomanip>
 using namespace std;

 #define MAXVEX 1001

 double matrix[MAXVEX][MAXVEX];
 double D[MAXVEX];

 int n;

 void Dijkstral(int v0)
 {
           int v,w,k=;
           double max;
           int final[MAXVEX];

           for(int i = ;i<=n;i++)
           {
                     D[i] = matrix[v0][i];
                     final[i] = ;
           }

           final[v0] = ;

           for(v=;v<=n;v++)
           {
                     max = -;
                     for(w=;w<=n;w++)
                     {
                               if(D[w]>max && !final[w])
                               {
                                        max = D[w];
                                        k = w;
                               }
                     }

                     final[k] = ;

                     for(w=;w<=n;w++)
                     {
                               if(max*matrix[k][w]>D[w] && !final[w])
                               {
                                         D[w]=max*matrix[v][w];
                               }
                     }
           }

 }

 int main()
 {
           while(cin>>n)
           {
                     for(int i = ;i<=n;i++)
                     {
                               for(int j = ;j<=n;j++)
                                         cin>>matrix[i][j];
                     }

                     int m;
                     cin>>m;
                     while(m--)
                     {
                               int a,b;
                               cin>>a>>b;

                               Dijkstral(a);

                               if(D[b])
                                         cout<<fixed<<setprecision()<<D[b]<<endl;
                               else
                                         cout<<"What a pity!\n";
                     }
           }
           return ;
 }

ac了，1482MS

 #include <cstdio>
 using namespace std;
 const int L = ;
 const int INF = <<;

 double map[L][L];
 int vis[L];
 double dis[L];

 int n,m;

 void Dijkstra(int s)
 {
           int i,j,k;
           double max;
           for(i = ;i<=n;i++)
           {
                     dis[i] = map[s][i];
                     vis[i] = ;
           }

           vis[s] = ;
           dis[s] = ;

           for(i = ;i<=n;i++)
           {
                     max = ;
                     for(j = ;j<=n;j++)
                     {
                               if(dis[j]>max && !vis[j])
                               {
                                         k = j;
                                         max = dis[j];
                               }
                     }

                     vis[k] = ;

                     for(j = ;j<=n;j++)
                     {
                               if(dis[j] < max*map[k][j] && !vis[j])
                               {
                                         dis[j] = max*map[k][j];
                               }
                     }
           }
 }

 void init()
 {
           int i,j;
           for(i = ;i<=n;i++)
           {

                     for(j = ;j<=n;j++)
                     {
                               scanf("%lf",&map[i][j]);
                     }
           }
 }

 int main()
 {
           while(scanf("%d",&n)!=EOF)
           {
                     int r,t;

                     init();

                     scanf("%d",&r);
                     while(r--)
                     {
                               int a,b;
                               scanf("%d%d",&a,&b);
                               Dijkstra(a);
                               if(dis[b])
                                         printf("%.3lf\n",dis[b]);
                               else
                                         printf("What a pity!\n");
                     }

           }

           return ;
 }