for (int j = i + 1; j <= 20; j++) {
        assertEquals(expectedSet.subSet(i, false, j, false), asSet.subSet(i, false, j, false));
        assertEquals(expectedSet.subSet(i, true, j, false), asSet.subSet(i, true, j, false));
        assertEquals(expectedSet.subSet(i, false, j, true), asSet.subSet(i, false, j, true));
        assertEquals(expectedSet.subSet(i, true, j, true), asSet.subSet(i, true, j, true));
      }
    }
  }

    }
  }

  /**
   * Returns the set of all possible subsets of {@code set}. For example, {@code
   * powerSet(ImmutableSet.of(1, 2))} returns the set {@code {{}, {1}, {2}, {1, 2}}}.
   *
   * <p>Elements appear in these subsets in the same iteration order as they appeared in the input
   * set. The order in which these subsets appear in the outer set is undefined. Note that the power

    SortedSet<String> subset = elementSet.subSet("b", "f");
    assertThat(subset).containsExactly("b", "c", "d", "e").inOrder();

    assertTrue(subset.remove("c"));
    assertThat(elementSet).containsExactly("a", "b", "d", "e", "f").inOrder();
    assertThat(subset).containsExactly("b", "d", "e").inOrder();
    assertEquals(10, ms.size());

    assertFalse(subset.remove("a"));

    assertEquals(ImmutableSortedSet.of(4, 6, 8, 10), Sets.subSet(set, Range.atLeast(4)));
    assertEquals(ImmutableSortedSet.of(8, 10), Sets.subSet(set, Range.atLeast(7)));
    assertEquals(empty, Sets.subSet(set, Range.atLeast(20)));

    assertEquals(set, Sets.subSet(set, Range.greaterThan(0)));
    assertEquals(ImmutableSortedSet.of(6, 8, 10), Sets.subSet(set, Range.greaterThan(4)));

    assertThat(set.subSet(1, 4)).containsExactly(1, 2, 3).inOrder();
    assertThat(set.subSet(2, 4)).containsExactly(2, 3).inOrder();
    assertThat(set.subSet(3, 4)).containsExactly(3).inOrder();
    assertThat(set.subSet(3, 3)).isEmpty();
    assertThat(set.subSet(2, 3)).containsExactly(2).inOrder();
    assertThat(set.subSet(1, 3)).containsExactly(1, 2).inOrder();

    SortedSet<String> subset = elementSet.subSet("b", "f");
    assertThat(subset).containsExactly("b", "c", "d", "e").inOrder();

    assertTrue(subset.remove("c"));
    assertThat(elementSet).containsExactly("a", "b", "d", "e", "f").inOrder();
    assertThat(subset).containsExactly("b", "d", "e").inOrder();
    assertEquals(10, ms.size());

    assertFalse(subset.remove("a"));

    assertThat(set.subSet(1, 4)).containsExactly(1, 2, 3).inOrder();
    assertThat(set.subSet(2, 4)).containsExactly(2, 3).inOrder();
    assertThat(set.subSet(3, 4)).containsExactly(3).inOrder();
    assertThat(set.subSet(3, 3)).isEmpty();
    assertThat(set.subSet(2, 3)).containsExactly(2).inOrder();
    assertThat(set.subSet(1, 3)).containsExactly(1, 2).inOrder();

   * boolean, Object, boolean)} method. If you override {@link #subSet(Object, boolean, Object,
   * boolean)}, you may wish to override {@link #subSet(Object, Object)} to forward to this
   * implementation.
   */
  @Override
  protected SortedSet<E> standardSubSet(
      @ParametricNullness E fromElement, @ParametricNullness E toElement) {

    powerSet = Sets.powerSet(set);
  }

  @Benchmark
  int iteration(int reps) {
    int sum = 0;
    for (int i = 0; i < reps; i++) {
      for (Set<Integer> subset : powerSet) {
        for (Integer value : subset) {
          sum += value;
        }
      }
    }
    return sum;
  }

    SortedSet<String> set = of("e");
    assertTrue(set.subSet("c", "g") instanceof ImmutableSortedSet);
    assertThat(set.subSet("c", "g")).contains("e");
    assertThat(set.subSet("e", "g")).contains("e");
    assertSame(this.<String>of(), set.subSet("f", "g"));
    assertSame(this.<String>of(), set.subSet("c", "e"));
    assertSame(this.<String>of(), set.subSet("c", "d"));
  }

  public void testSingle_first() {