public class Main {
  static void printArray(Obj a[]) {
    for (int i=0; i<a.length; i++) {
      a[i].print();
      System.out.println();
    }
  }
  public static void main(String [] args) {
    Obj signed1 = new Signed(5);
    Person person1 = new Person(1234567890L,"Jane Doe");
    
    signed1.print();
    Signed.print((Signed)signed1);
    System.out.println();
    person1.print();
    System.out.println();
    System.out.println();
    Obj a[]=new Obj[3];
    a[0] = signed1;
    a[1] = person1;
    a[2] = new Signed(9);
    printArray(a);
    System.out.println();
    Student student1=new Student(9876543210L,"John Smith",1499999);
    Student.print(student1);
    System.out.println();
    Person.print(student1);
    System.out.println();
    student1.print();
    System.out.println();
    System.out.println();
    a[2] = student1;
    printArray(a);
  }
}