#include <iostream>

#include <cstdio>

#include <sstream>

#include <map>

#include <string>

#include <algorithm>

using namespace std;

string str[105];

string sstr[105];

int main(){

	int T,kase=0,n,t1,t2;	double ans,par;

	scanf("%d",&T);

	while(T--){

		scanf("%d",&n);

		getchar();

		for(int i=1;i<=n;i++)

		getline(cin,str[i]);

		for(int i=1;i<=n;i++)

		getline(cin,sstr[i]);

		ans=0;

		for(int i=1;i<=n;i++){

			par=0;

			map<string,int>M;

			stringstream sin(str[i]);

			string c;

			t1=t2=0;

			sin>>c;

			while(sin>>c){

				M[c]=1;

				t1++;

			}

			if(t1==0) continue;

			stringstream csin(sstr[i]);

			csin>>c;

			int j=0;

			while(csin>>c){

				t2++;

				if(M.find(c)!=M.end()){

					j++;

					par+=(double)j/t2;

				}

			}

			ans+=(par/t1);

		}

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

	}

}