AA                                                                                                                                                                                                                                                                                                                                                                                                                                101
                                                                                                                                                                                                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                                                                                                                                                                                                              
                                                                                                         A                                                                                                                                                                                                                  100                                                                                                               
                                                                                                                                                                                            count                                                                                                                                                                                                                                             
                                                                                                                                                                                                                                                                                                                                                                                                                                              
         AB                                                                                                                                                                                                                                                                                                                                                                                                                                102
                                                                                                                                                                                                                                                                                                                                                                                                                                              
                                                                                                         B                                                                                                                                                                                                                  200