public static RandomNode[] MakeRange(params int[][] args)
        {
            RandomNode[] ln = new RandomNode[args.Length];
            for (int i = 0; i < args.Length; i++)
            {
                int[] ints = args[i];
                ln[i] = RandomNode.Make(ints);
            }

            return(ln);
        }
        public static RandomNode Make(params int[] args)
        {
            RandomNode root = new RandomNode(args[0]);
            RandomNode next = root;

            for (int i = 1; i < args.Length; i++)
            {
                RandomNode newNode = new RandomNode(args[i]);
                next.next = newNode;
                next      = next.next;
            }

            return(root);
        }
        public override string ToString()
        {
            StringBuilder b = new StringBuilder();

            b.Append($"{this.val} => ");
            RandomNode next = this.next;

            while (next != null)
            {
                b.Append($"{next.val} => ");
                next = next.next;
            }

            b.Append($"# ");
            return(b.ToString());
        }