static void Main(string[] args)
{
SerialNumber first = new SerialNumber("56AAA7105A25");
SerialNumber second = new SerialNumber("57AAA71064C6");
SerialNumber third = new SerialNumber("58AAA71064D6");
Console.WriteLine(first.CompareTo(second));
Console.WriteLine(second.CompareTo(third));
Console.ReadLine();
}