public void Array4()
        {
            Person[] p = new Person[5];

            p [0] = new Person ("Sijo", "Varghese", 20);
            p [1] = new Person ("Abhi", "Kumar", 10);
            p [2] = new Person ("Abhi", "Bachhan", 50);
            p [3] = new Person ("John", "Cena", 17);
            p [4] = new Person ("Jimmy", "Anderson", 67);

            Array.Sort(p,Person.SortByName);

            for (int j = 0; j < p.Length; j++) {

                Console.WriteLine("FirstName :{0} \nLastName :{1}\nAge :{2}\n ",p[j].FirstName,p[j].LastName,p[j].Age);

            }
        }
        public void Array3()
        {
            Person[] p = new Person[5];
            for (int i = 0; i < 5; i++) {
                p [i] = new Person ();
                p[i].FirstName="FName"+(i+1).ToString();
                p [i].LastName = "LName" + (i + 1).ToString();

            }

            p [0].Age = 20;
            p [1].Age = 10;
            p [2].Age = 50;
            p [3].Age = 17;
            p [4].Age = 67;

            Array.Sort (p);

            for (int j = 0; j < p.Length; j++) {
                Console.WriteLine("FirstName :{0} \nLastName :{1}\nAge :{2}\n ",p[j].FirstName,p[j].LastName,p[j].Age);

            }
        }