docs: public void intersect(OpenBitSet other) {
          int newLen= Math.min(this.wlen,other.wlen);
          long[] thisArr = this.bits;
          long[] otherArr = other.bits;
          // testing against zero can be more efficient
          int pos=newLen;
          while(--pos>=0) {
              thisArr[pos] &= otherArr[pos];
          }
          if (this.wlen > newLen) {
              // fill zeros from the new shorter length to the old length
              Arrays.fill(bits,newLen,this.wlen,0);
          }
          this.wlen = newLen;
      }