bbbb bcbc bccc bcuc bobb bobo bobu bock boco bocu boko boku boob booc book bouk bubb bubo bubu bucc buck buco bucu bukk buko buku c-bo cbbc cbcc cbcu cbko ccbc cccb cccc cccu ccob ccoc ccuc ckbc ckck ckco ckob ckoc ckoo cobb cobo cobu cock coco cocu cok- coko coob cook coub couk cub- cubb cucc cuck cuk- kbbb kbbc kbbk kbbo kbbu kbcb kbck kbco kbcu kbkb kbkk kbko kbob kboc kbok kboo kbub kbuc kbuk kbuu kcbc kcbk kcbu kccb kccc kcck kccu kckc kckk kcko kcob kcou kcub kcuk kkbb kkbo kkcb kkck kkco kkkk kkob kkoo kkuu kobb kobc kobk kobo kobu kocb kock kokb kokc kokk koko koku koob kooc kook kooo koou koub kouu kubb kubc kubo kubu kucb kucc kuco kukk kuku kuok kuoo kuub kuuk kuuu obbo obkb obok ocbc occc okcu okko okok ooku oooo oucc ouu- ubbo uboc ucbc ukcc ukko ukok uocc uuoc uuuu