static void Main(string[] args)
{
Client firstClient = new Client("John", "Snow", 123569);
Account firstClientAccount = new Account(firstClient, AccountType.Gold);
Console.WriteLine(firstClient.FirstName);
Console.WriteLine(firstClient.LastName);
Console.WriteLine(firstClient.CreditCard);
firstClientAccount.Put(10000);
Console.WriteLine(firstClientAccount.Sum);
Console.WriteLine(firstClientAccount.BonusPoints);
}