b-u bbb bbd bbk bbn bbo bbu bby bdb bdd bdk bdo bdu bdy bkb bkk bkn bko bnb bnd bnk bnn bno bnu bob bod bok bon boo bou boy bub bud buk bun buo buu buy by- byd byk byn byo byu dbb dbd dbk dbn dbo dbu dby ddb ddd ddk ddn ddo ddu ddy dkb dkk dko dku dnb dnd dnk dnn dno dny dob dod dok don doo dou doy dub dud duk dun duo duy dy- dyb dyd dyk dyn dyo dyu dyy kbb kbd kbk kbn kbo kbu kdb kdk kdo kdu kdy kkb kkk kkn kku kky kn- knd knk knn kno knu kob kod kok kon koo kou koy kub kud kuk kun kuu kuy kyd kyn kyo kyu nbb nbd nbk nbn nbo nbu ndb ndd ndk ndn ndo ndu ndy nkk nkn nko nku nky nnb nnk nnn nno nnu no- nob nod nok non noo nou noy nub nud nuk nun nuo nuu nuy nyd nyk nyn nyo nyu nyy ob- obb obd obk obn obo obu oby odb odd odn odo odu okb okd okk oko oku on- onb ond onk onn ono onu ony oo- oob ood ook oon ooo ou- oud ouk oun ouo oyd oyo ubb ubk ubn ubo ubu uby udb udd udk udn udo udu ukb ukk ukn uku un- unb und unk unn uno unu uny uob uod uok uon uoo uun uuu uyo uyu yby ydn ydo ydy ykk ykn ynd ynk ynn ynu yny yob yod yok yon yoo you yoy yud yuk yun yuo yuu yuy yyb yyu yyy