some condition                                                                                   
                                                                                                                                 
                                                                                                                              yes
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                some condition                                                                                   
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                              yes
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                some condition                                                                                   
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                                 
                                                                                                                              yes