static void Main(string[] args) { StudentService service = new StudentService(); service.Add(new Student { Name = "Andrii", Age = 16, LastName = "Pashko", }); service.Add(new Student { Name = "Petro", Age = 23, LastName = "Pavlov", }); Random rnd = new Random(); foreach (Student item in service.Students) { item.AddMark("C++", rnd.Next(1, 12)); item.AddMark("C#", rnd.Next(1, 12)); } foreach (var item in service.Students) { Console.WriteLine(item); } service.Save(); service.Best(); }