docs: @Override
    public long getLongCardinality() {
      if (doCacheCardinalities) {
        if (highToBitmap.isEmpty()) {
          return 0L;
        }
        int indexOk = ensureCumulatives(highestHigh());
  
        // ensureCumulatives may have removed empty bitmaps
        if (highToBitmap.isEmpty()) {
          return 0L;
        }
  
  
        return sortedCumulatedCardinality[indexOk - 1];
      } else {
        long cardinality = 0L;
        for (BitmapDataProvider bitmap : highToBitmap.values()) {
          cardinality += bitmap.getLongCardinality();
        }
        return cardinality;
      }
    }