abstract class Person implements Comparable<Person> {
    protected String lastName, firstName;

    public Person(String lastName, String firstName) {
        this.lastName = lastName;
        this.firstName = firstName;
    }

    public String fullName() { return firstName+" "+lastName; }

    protected abstract int rank();

    public compareTo(Person o) {
        int r1 = this.rank(), r2 = o.rank();
        return r1 != r2 ? r1-r2 : this.fullName().compareTo(o.fullName());
    }
}

class Instructor extends Person {
    protected int rank() { return 5; }
}

class TeachingAssistant extends Person {
    protected int rank() { return 10; }
}

class Student extends Person {
    protected int rank() { return 15; }
}