int index =
        SortedLists.binarySearch(
            ranges,
            Range::lowerBound,
            Cut.belowValue(key),
            KeyPresentBehavior.ANY_PRESENT,
            KeyAbsentBehavior.NEXT_LOWER);
    if (index == -1) {
      return null;
    } else {
      Range<K> range = ranges.get(index);
      return range.contains(key) ? values.get(index) : null;
    }
  }

  @Override