inc                                                                                                                                                                                                                               no                                      
                                           A                                                                                              B                                                                        C                                                                            D                                                                    
                                                                                                                                                                                                                                                                                                                                                                     
                                                     yes                                                                                           out                                                                       yes                                                                         yes                                                         
                                                                                                                                                                                                                                                                                                                                                                     
                                                                                                                                                                                                                                                                                                                                                                     
                                                                                                                                                                                                                                                                                                                                                                   EE
                                     AA                                                                                             BB                                                                       CC                                                                           DD