docs: public static MutableRoaringBitmap naive_and(ImmutableRoaringBitmap... bitmaps) {
      MutableRoaringBitmap answer;
  
      if (bitmaps.length > 0) {
        answer = (bitmaps[0]).toMutableRoaringBitmap();
        for (int k = 1; k < bitmaps.length; ++k) {
          answer = ImmutableRoaringBitmap.and(answer, bitmaps[k]);
        }
      } else {
        answer = new MutableRoaringBitmap();
      }
  
      return answer;
    }