贪心/poj 1018 Communication System

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<algorithm>
 4 using namespace std;
 5 const int INF=0xfffffff;
 6 struct node
 7 {
 8     int b,p;
 9 };
10 node a[110][110];
11 int m[110];
12 int pmin,psum,bmax,n;
13 double ans;
14 int main()
15 {
16     int T;
17     scanf("%d",&T);
18     for (int t=1;t<=T;t++)
19     {
20         memset(a,0,sizeof(a));
21         memset(m,0,sizeof(m));
22         ans=0.0;
23         scanf("%d",&n);
24         for (int i=1;i<=n;i++)
25         {
26             scanf("%d",&m[i]);
27             for (int j=1;j<=m[i];j++)
28             {
29                 scanf("%d%d",&a[i][j].b,&a[i][j].p);
30             }
31         }
32         for (int i=1;i<=n;i++)
33             for (int j=1;j<=m[i];j++)
34         {
35             bmax=a[i][j].b;
36             bool flag=0;
37             psum=a[i][j].p;
38             for (int k=1;k<=n;k++)
39             {
40                 if (k==i) continue;
41                 pmin=INF;
42                 for (int q=1;q<=m[k];q++)
43                     if (a[k][q].b>=bmax && a[k][q].p<pmin)
44                     {
45                         pmin=a[k][q].p;
46                       //  flag=1;
47                     }
48                // if (!flag) break;
49                 psum+=pmin;
50             }
51           //  if (!flag) break;
52             if (ans<(double)bmax/psum) ans=(double)bmax/psum;
53         }
54         printf("%.3f\n",ans);
55     }
56     return 0;
57 }