comefrom: <doocs>1239.Maximum Length of a Concatenated String with Unique Characters_1.py
code: def ones_count(x):
      c = 0
      while x:
          x &= x - 1
          c += 1
      return c
masked: def sample_funcname ( var_0 ) :
      var_2 = 0
      while var_0 :
          var_0 &= var_0 - 1
          var_2 += 1
      return var_2
  