class Person implements Comparable<Person>{

    private int alder;

    public Person(int alder) {
        this.alder = alder;
    }

    // skal navn, alder ++

    public int hentAlder() {
        return alder;
    }


    public int compareTo(Person annen) {
        return alder - annen.hentAlder(); // > 0 om alder > annen.hentAlder();
        // < 0
    }
}