#include <iostream>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <vector>

using namespace std;

const int max_n = 15;

int n;
double len[max_n], p[max_n + max_n][2], dp[max_n + max_n][1 << max_n];
vector< int > mask[max_n];

inline double dist(double x1, double y1, double x2, double y2) {
    return sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
}

int main() {
    int test = 1;
    while (scanf("%d", &n)) {
        if (n == 0)
            break;
        for (int i = 0;i < n;i++)
            scanf("%lf %lf %lf %lf", &p[i][0], &p[i][1], &p[n + i][0], &p[n + i][1]);
        for (int i = 0;i < n;i++)
            len[i] = dist(p[i][0], p[i][1], p[n + i][0], p[n + i][1]);
        for (int i = 0;i < n + n;i++) {
            for (int j = 0;j < (1 << n);j++) {
                dp[i][j] = 1e5;
            }
        }
        for (int i = 0;i < max_n;i++)
            mask[i].clear();
        for (int i = 0;i < (1 << n);i++)
            mask[__builtin_popcount(i)].push_back(i);
        for (int i = 0;i < n;i++)
            dp[i][1 << i] = dp[n + i][1 << i] = len[i];
        for (int i = 2;i <= n;i++) {
            for (int j = 0;j < mask[i].size();j++) {
                int m = mask[i][j];
                for (int k = 0;k < n + n;k++) {
                    int q = (k < n)? k: k - n;
                    if ((m & (1 << q)) == 0)
                        continue;
                    int o = (k < n)? k + n: k - n;
                    for (int l = 0;l < n + n;l++) {
                        int d = (l < n)? l: l - n;
                        if (d == q || (m & (1 << d)) == 0)
                            continue;
                        dp[k][m] = min(dp[k][m], dp[l][m ^ (1 << q)] + dist(p[l][0], p[l][1], p[o][0], p[o][1]) + len[min(k, o)]);
                    }
                }
            }
        }
        double ans = 1e5;
        for (int i = 0;i < n + n;i++)
            ans = min(ans, dp[i][(1 << n) - 1]);
        printf("Case %d: %.5lf\n", test++, ans);
    }
    return 0;
}