docs: public int last()
      {
          for (int ii=array.length-1;ii>=0;ii--)
          {
              if (array[ii] != 0)
              {
                  for (int jj=Math.min(bits,(ii+1)*8)-1;jj>=0;jj--)
                  {
                      if (isSet(jj))
                      {
                          return jj;
                      }
                  }
              }
          }
          return -1;
      }