public static int Sum(this MySet set)
        {
            int len = 0;

            foreach (string item in set.GetHash())
            {
                len += item.Length;
            }
            return(len);
        }
        public static int Max(this MySet set)
        {
            int len = set.GetItemByIndex(0).Length;

            foreach (string item in set.GetHash())
            {
                if (len < item.Length)
                {
                    len = item.Length;
                }
            }
            return(len);
        }