static void Main(string[] args)
{
//Person p1 = new Person() { Name = "Mario"};
//p1.Id = 2;
//p1.SayHi();
//Person p1 = new Person(1, "aa");
//Employee ee = new Employee()
Employee e1 = new Employee(3, "aa", 123);
//e1.Id = 3;
//e1.Salary = 123M;
//e1.SayHi();
Student s = new Student();
s.SayHi();
//Printperson(p1);
// Printperson(e1);
//Person p = new Employee();
}