//public static void Main(string[] args)
        //{
        //    string s;
        //    var inputs = new List<string>();
        //    while ((s = Console.ReadLine()) != null)
        //        inputs.Add(s);

        //    foreach (var result in Answer(inputs.ToArray()))
        //        Console.WriteLine(result);
        //}

        public static IList <string> Answer(IList <string> inputs)
        {
            var gis             = Inputs.AdjacencyListGraphDecimal(inputs);
            var pointsWithCount = gis.ToPoints();
            var k = gis.NextAsInt();

            var pointCount = pointsWithCount.Item1;
            var points     = pointsWithCount.Item2.ToArray();
            var lines      = PrimsAlgorithm.ConnectAllPoints(pointCount, points);

            var g           = gis.ToUndirectedAdjacencyGraph(new Tuple <int, IEnumerable <Edge <decimal> > >(pointCount, lines));
            var primsResult = PrimsAlgorithm.Calculate(g);

            var d = primsResult.Cost.Values
                    .OrderByDescending(i => i)
                    .Take(k - 1)
                    .Last();


            var answer = d.ToString("0.0000000000");

            answer = answer.Remove(answer.Length - 1);  //Simulate truncate at 9
            return(new[] { answer });

            //return new[] { answer.ToString("0.000000000") };
        }
        //public static void Main(string[] args)
        //{
        //    string s;
        //    var inputs = new List<string>();
        //    while ((s = Console.ReadLine()) != null)
        //        inputs.Add(s);

        //    foreach (var result in Answer(inputs.ToArray()))
        //        Console.WriteLine(result);
        //}

        public static IList <string> Answer(IList <string> inputs)
        {
            var gis             = Inputs.AdjacencyListGraphDecimal(inputs);
            var pointsWithCount = gis.ToPoints();
            var pointCount      = pointsWithCount.Item1;
            var points          = pointsWithCount.Item2.ToArray();

            var lines = PrimsAlgorithm.ConnectAllPoints(pointCount, points);
            var g     = gis.ToUndirectedAdjacencyGraph(new Tuple <int, IEnumerable <Edge <decimal> > >(pointCount, lines));

            var primsResult = PrimsAlgorithm.Calculate(g);
            var answer      = primsResult.Cost.Values.Sum();

            return(new [] { answer.ToString("0.000000000") });
        }