import java.util.*;

public class Connect
{
	public static void main( String[] arg )
	{
		int nCase = 1;
		for(Scanner sc = new Scanner(System.in) ;; ++nCase)
		{
			int N = sc.nextInt();
			if( N == 0 )
				return;

			assert 2<=N && N<=14 : "\n    N (number of linesegs) is out-of-range";

			double sumlen = 0;
			double[] xa = new double[N];
			double[] ya = new double[N];
			double[] xb = new double[N];
			double[] yb = new double[N];
			for(int i=0; i<N; ++i)
			{
				xa[i] = sc.nextDouble();
				ya[i] = sc.nextDouble();
				xb[i] = sc.nextDouble();
				yb[i] = sc.nextDouble();

				assert -100<=xa[i] && xa[i]<=100 : "\n    Coordinate is out-of-range";
				assert -100<=ya[i] && ya[i]<=100 : "\n    Coordinate is out-of-range";
				assert -100<=xb[i] && xb[i]<=100 : "\n    Coordinate is out-of-range";
				assert -100<=yb[i] && yb[i]<=100 : "\n    Coordinate is out-of-range";

				sumlen += len(xa[i], ya[i], xb[i], yb[i]);
			}

			// solve
			Map<Integer,Double> m = new HashMap<Integer,Double>();

			// singleton case
			for(int i=0; i<N; ++i)
			{
				m.put( (1<<i) | (2*i+0<<N), 0.0 );
				m.put( (1<<i) | (2*i+1<<N), 0.0 );
			}

			// add one by one
			for(int num=2; num<=N; ++num)
			{
				Map<Integer,Double> m2 = new HashMap<Integer,Double>();
				for( Map.Entry<Integer,Double> kv : m.entrySet() )
				{
					int    k  = kv.getKey();
					int    ks = k & (1<<N)-1;
					int    ki = k >> N;
					double kx = ((ki&1)==0 ? xa : xb)[ki>>1];
					double ky = ((ki&1)==0 ? ya : yb)[ki>>1];
					double v  = kv.getValue();
					for(int i=0; i<N; ++i)
						if( (ks & (1<<i)) == 0 )
						{
							int    k2 = ks|(1<<i) | (2*i+0<<N);
							double v2 = v + len(kx, ky, xb[i], yb[i]);
							if( !m2.containsKey(k2) || m2.get(k2)>v2 )
								m2.put( k2, v2 );

							k2 = ks|(1<<i) | (2*i+1<<N);
							v2 = v + len(kx, ky, xa[i], ya[i]);
							if( !m2.containsKey(k2) || m2.get(k2)>v2 )
								m2.put( k2, v2 );
						}
				}
				m = m2;
			}

			// find the minimum
			double v = Double.MAX_VALUE;
			for( double vv : m.values() )
				v = Math.min( v, vv );

			System.out.printf( "Case %d: %.9f\n", nCase, v+sumlen );
		}
	}

	static double len(double x, double y, double X, double Y)
	{
		return Math.sqrt( (x-X)*(x-X) + (y-Y)*(y-Y) );
	}
}