Method main

equalshashcode/IndividualTest.java:10–17

(String[] args)

public class IndividualTest {
  public static void main(String[] args) {
    Set<Individual> pets = new TreeSet<>();
    for(List<? extends Pet> lp :
        MapOfList.petPeople.values())
      for(Pet p : lp)
        pets.add(p);
    pets.forEach(System.out::println);
  }
}
/* Output:
Cat Elsie May