int main ( void )
{
  int i = 0;
  int j = 0;
  int k = 0;

  //...

  switch ( i )
  {
    case 1:                //遵循1
      if ( j > 0 )
      {
        k = 1;
        break;
      }
      k = 2;
      break;
    case 2:  /* shared */  //遵循2
    case 3:                //遵循3
    {
      j = 3;
    }
      break;
    case 4:  /* shared */  //遵循4
      k = 4;
    case 5:
      j = 5;
      break;
    default:               //遵循5
      j = -1;
      break;
  }

  return ( 0 );
}