class Persoana implements Comparable<Persoana>
{
    private String nume;
    private int varsta;

    public Persoana(String n, int v)
    {
        nume = n;
        varsta = v;
    }

    public String getNume()
    {
        return nume;
    }

    public int compareTo(Persoana p)
    {
        return nume.compareTo(p.getNume());
    }

    public String toString()
    {
        return nume;
    }
}

class Main
{
    public static void main(String[] args)
    {
        SortedSet<Persoana> set = new TreeSet<Persoana>(
            new Comparator<Persoana>()
            {
                public int compare(Persoana p1, Persoana p2)
                {
                    return p1.getNume().compareTo(p2.getNume());
                }
            });

        set.add(new Persoana("B", 10));
        set.add(new Persoana("A", 15));
        set.add(new Persoana("C", 20));

        System.out.println(set);
    }
}