import java.util.Comparator;

/** PersonComparator.java -  How do we compare names of people?  
 *  Check the last names first.
 */
public class PersonComparator implements Comparator
{
  public int compare(Object o1, Object o2)
  {
    Person p1 = (Person) o1;
    Person p2 = (Person) o2;

    String first1 = p1.getFirst();
    String first2 = p2.getFirst();
    String last1 = p1.getLast();
    String last2 = p2.getLast();

    if (last1.compareTo(last2) < 0)
      return -1;
    else if (last1.compareTo(last2) > 0)
      return 1;
    else
    {
      if (first1.compareTo(first2) < 0)
        return -1;
      else if (first1.compareTo(first2) > 0)
        return 1;
      else
        return 0;
    }
  }  
}