#include<cstdio>

 #include<cstring>

 #include<iostream>

 #include<algorithm>

 #include<cmath>

 using namespace std;

 const int maxn=;

 int main()

 {

     int T,n;

     cin>>T;

     for(int cas=;cas<=T;cas++)

     {

         double x1,y1,x2,y2,x3,y3,v;

         scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2);

         scanf("%lf%lf%lf",&x3,&y3,&v);

         double ans;

         double tmax=-1e7,tmin=1e7;

         if((fabs(y3)<1e-))

         {

             tmax=max(x1,x2);

             tmin=min(x1,x2);

             if(tmin>v||tmax<v)

                 x1=*v-x1;

             ans=fabs(x1-x2)*fabs(x1-x2)+fabs(y1-y2)*fabs(y1-y2);

                 ans=sqrt(ans);

         }else{

             tmax=max(y1,y2);

             tmin=min(y1,y2);

             if(tmin>v||tmax<v)

                 y1=*v-y1;

             ans=fabs(x1-x2)*fabs(x1-x2)+fabs(y1-y2)*fabs(y1-y2);

                 ans=sqrt(ans);

         }

         printf("Case #%d: %.6lf\n",cas,ans);

     }

     return ;

 }