C++编程之美-数字之魅(代码清单2-4)

int Count(BYTE v)
{
     int num = 0;
     switch (v)
     {
          case 0x0:
               num = 0;
               break;
          case 0x1:
          case 0x2:
          case 0x4:
          case 0x8:
          case 0x10:
          case 0x20:
          case 0x40:
          case 0x80:
               num = 1;
               break;
          case 0x3:
          case 0x6:
          case 0xc:
          case 0x18:
          case 0x30:
          case 0x60:
          case 0xc0:
               num = 2;
               break;
               //...
      }
      return num;     
}