1 #include<iostream>
 2 #include<cstdio>
 3 #include<cmath>
 4 using namespace std;
 5 double map[1010][1010],node[1010],s,Min;
 6 int m,flag;
 7 const double INF=999999;
 8 
 9 void prim()
10 {
11     int vis[1010]= {0};
12     int tm=1,v=1;
13     flag=0;
14     s=0;
15     vis[tm]=1;
16     node[tm]=0;
17     for (int k=1; k<=m; k++)
18     {
19         Min=INF;
20         for (int i=1; i<=m; i++)
21             if (!vis[i])
22             {
23                 //cout<<node[i]<<" "<<map[tm][i]<<endl;
24                 if(node[i]>map[tm][i]&&map[tm][i]>=10&&map[tm][i]<=1000)
25                     node[i]=map[tm][i];
26                 if (Min>node[i])
27                 {
28                     Min=node[i];
29                     v=i;
30 
31                 }
32             }
33         //s+=node[v];
34         vis[v]=1;
35         tm=v;
36     }
37     for (int i=1; i<=m; i++)
38     {
39         s+=node[i];
40         if (node[i]!=INF)
41             flag++;
42     }
43 }
44 
45 int main ()
46 {
47     int n,a[1010],b[1010];
48     cin>>n;
49     while (n--)
50     {
51         //memset (map,INF,sizeof (map));
52         cin>>m;
53         for (int i=1; i<=m; i++)
54         {
55             cin>>a[i]>>b[i];
56         }
57         for(int i=1; i<=m; i++)
58         {
59             node[i]=INF;
60             for (int j=1; j<=m; j++)
61             {
62                 map[i][j]=map[j][i]=sqrt((double)((a[i]-a[j])*(a[i]-a[j])+(b[i]-b[j])*(b[i]-b[j])));
63             }
64         }
65         prim();
66         if (flag==m)
67             printf ("%.1lf\n",s*100);
68         else
69             printf ("oh!\n");
70     }
71     return 0;
72 }