#include <stack>
#include <cstdio>
#include <list>
#include <set>
#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <functional>
#include <cstring>
#include <algorithm>
#include <cctype>
#include <string>
#include <map>
#include <cmath>
using namespace std;
#define LL long long
#define ULL unsigned long long
#define SZ(x) (int)x.size()
#define Lowbit(x) ((x) & (-x))
#define MP(a, b) make_pair(a, b)
#define MS(arr, num) memset(arr, num, sizeof(arr))
#define PB push_back
#define X first
#define Y second
#define ROP freopen("input.txt", "r", stdin);
#define MID(a, b) (a + ((b - a) >> 1))
#define LC rt << 1, l, mid
#define RC rt << 1|1, mid + 1, r
#define LRT rt << 1
#define RRT rt << 1|1
const double PI = acos(-1.0);
const int INF = 0x3f3f3f3f;
const double eps = 1e-8;
const int MAXN = 1000 + 10;
const int MOD = 29;
const int dir[][2] = { {-1, 0}, {0, -1}, { 1, 0 }, { 0, 1 } };
int cases = 0;
typedef pair<int, int> pii;
 
double dp[MAXN], p[MAXN];
 
int main()
{
    //ROP;
    int T;
    scanf("%d", &T);
    while (T--)
    {
        MS(dp, 0);
        int n, k, m;
        scanf("%d%d%d", &n, &k, &m);
        for (int i = 0; i < n; i++) scanf("%lf", &p[i]);
        dp[0] = 0; dp[1] = p[0];
        for (int i = 2; i <= m; i++)
            for (int j = 0; j < n; j++) dp[i] += p[j] * pow(dp[i-1], j);
        printf("Case #%d: %.9f\n", ++cases, pow(dp[m], k));
    }
    return 0;
}