docs: public int andCardinality(MappeableContainer x) {
      if (this.isEmpty()) {
        return 0;
      } else if (x.isEmpty()) {
        return 0;
      } else {
        if (x instanceof MappeableArrayContainer) {
          return andCardinality((MappeableArrayContainer) x);
        } else if (x instanceof MappeableBitmapContainer) {
          return andCardinality((MappeableBitmapContainer) x);
        }
        return andCardinality((MappeableRunContainer) x);
      }
    }