import java.io.*;
import java.util.Arrays;

public class s2011_r1c_b {
    public static void main(String[] args) throws IOException {
        new s2011_r1c_b().run();
    }
    int nextInt() throws IOException {
        in.nextToken();
        return (int) in.nval;
    }

    StreamTokenizer in;
    Writer writer;
    Reader reader;

    void run() throws IOException {
        boolean oj = System.getProperty("ONLINE_JUDGE") != null;
        reader = oj ? new InputStreamReader(System.in, "ISO-8859-1") : new FileReader("input/is2011_r1c_b.txt");
        writer = oj ? new OutputStreamWriter(System.out, "ISO-8859-1") : new FileWriter("output/os2011_r1c_b.txt");
        in = new StreamTokenizer(new BufferedReader(reader));
        PrintWriter out = new PrintWriter(writer);
        int T = nextInt();
        int cnt = 1;
        while (cnt <=T) {
            int L = nextInt();
            int t = nextInt();
            int N = nextInt();
            int[] arr = new int[N + 1];
            int C = nextInt();
            int[] koeff = new int[C];

            for (int i = 0 ; i < C; i++)
                koeff[i] = nextInt();


            int j = 0;
            for (int i = 1; i < arr.length; i++) {
                if (j == koeff.length)
                    j = 0;
                arr[i] = koeff[j] ;
                j++;
            }
            boolean[] starHasBooster = new boolean[arr.length];
            // fill starHasBooster
            int[] backKoeff = Arrays.copyOf(koeff, koeff.length);
            Arrays.sort(backKoeff);
            for (int i = backKoeff.length - 1; i > -1; i--) {
                for (j = arr.length - 1; j > 0; j--)
                    if (arr[j] == backKoeff[i]) {
                        starHasBooster[j - 1] = true;
                        L--;
                        if (L == 0) break;
                    }
                if (L == 0) break;
            }
            double speed;
            long time = 0;
            for (int index = 1; index < arr.length; index++) {
                if (time < t) {
                    if (time + arr[index] * 2 > t && starHasBooster[index - 1]) {
                        double need = t - time;
                        time += need ;
                        time += arr[index] - need * 0.5;
                    } else {
                        time += arr[index] / 0.5;
                    }
                } else {
                    speed = starHasBooster[index - 1]? 1:0.5;
                    time += arr[index] / speed;
                }
            }

            out.println(String.format("Case #%d: ", cnt) + time);
            cnt++;
        }
        out.flush();
        out.close();
    }
}