case 0xfffffe:return 0;
      case 0xfffffd:return 1;
      case 0xfffffb:return 2;
      case 0xfffff7:return 3;
      case 0xffffef:return 4;
      case 0xffffdf:return 5;
      case 0xffffbf:return 6;
      case 0xffff7f:return 7;
      case 0xfffeff:return 8;
      case 0xfffdff:return 9;
      case 0xfffbff:return 10;
      case 0xfff7ff:return 11;
      case 0xffefff:return 12;
      case 0xffdfff:return 13;
      case 0xffbfff:return 14;
      case 0xff7fff:return 15;
      case 0xfeffff:return 16;
      case 0xfdffff:return 17;
//      case 0xfbffff:return 18;
//      case 0xf7ffff:return 19;
//      case 0xefffff:return 20;
//      case 0xdfffff:return 21;
      default:   return 0;
报错：MAIN.C(96): error C175: 0xFFFF: duplicate case value
从第17个就编译出错，请各位老师朋友帮我看看这段代码，错在什么地方？多谢指教！！