// A few elements.
    a = asList(4, 8, 15, 16, 23, 42);
    b = asList(4, 8, 15, 16, 23, 42);
    assertTrue(Iterators.elementsEqual(a.iterator(), b.iterator()));

    // The same, but with nulls.
    a = Arrays.<@Nullable Integer>asList(4, 8, null, 16, 23, 42);
    b = Arrays.<@Nullable Integer>asList(4, 8, null, 16, 23, 42);
    assertTrue(Iterators.elementsEqual(a.iterator(), b.iterator()));

   *
   * <pre>{@code
   * public static final ImmutableSortedSet<Number> LUCKY_NUMBERS =
   *     new ImmutableSortedSet.Builder<Number>(ODDS_FIRST_COMPARATOR)
   *         .addAll(SINGLE_DIGIT_PRIMES)
   *         .add(42)
   *         .build();
   * }</pre>
   *
   * <p>Builder instances can be reused; it is safe to call {@link #build} multiple times to build