public class Person
        {
            protected int[] a = new int[10];
            public int this [int index]
            {
                get { return a[index]; }
                set { a[index] = value; }
            }

            protected int age;
            protected string name, surname;
            protected static int ID = 0;

            public int Age
            {
                get { return age; }
                set {
                    // if (value < 0) throw new ArgumentOutOfRangeException();
                    if (value < 0)
                        value = 0;
                    age = value;

                }
            }

            public Person(int age, string name, string surname)
            {
                ID++;
                this.Age = age;
                this.name = name;
                this.surname = surname;
            }

            public void getInfromation()
            {
                Console.WriteLine("Age = " + age);
                Console.WriteLine("Name = " + name);
                Console.WriteLine("Surname = " + surname);
            }
        }