import java.util.*;

public class MinimumScalarProduct {

    public MinimumScalarProduct() {
    }

    public static void main(String[] args)
    {
    	Scanner sc = new Scanner(System.in);
    	int t,n,ctr=0,i,j;
    	long ans=0;
    	t = sc.nextInt();
    	for (i=1;i<=t;i++) //number of test cases
    	{
    		ans = 0;
    		n = sc.nextInt();
    		int nArray1[] = new int[n];
    		int nArray2[] = new int[n];

    		for (j=0;j<n;j++) //initialize array1
    		{
    			nArray1[j] = sc.nextInt();
    		}

    		for (j=0;j<n;j++) //initialize array2
    		{
    			nArray2[j] = sc.nextInt();
    		}

    		Arrays.sort(nArray1); //sort
			Arrays.sort(nArray2); //sort

			ctr = nArray2.length-1; //get last index of array2

    		for (j=0;j<n;j++)
    		{
    			ans += (long)(nArray1[j] * nArray2[ctr]);
    			ctr--;
    		}
    		System.out.println("Case #" + i + ": " + ans);
    	}
    }

}