b-u bbb bbi bbk bbl bbr bbu bi- bib bii bik bil bir biu bkb bkk bkl bkr blb bli blk bll blr blu brb bri brk brl brr bru bub bui buk bul bur buu ibb ibi ibk ibl ibr ibu iib iii iil iir iiu ikb iki ikk ikl ikr iku il- ilb ili ilk ill ilr ilu ir- irb iri irk irl irr iru iu- iub iui iur kbb kbi kbk kbl kbr kbu kib kii kik kil kir kiu kkb kki kkk kkl kkr kku kl- klb kli klr klu kri krk krl krr kru kub kui kuk kul kur kuu lbb lbi lbk lbl lbr lbu lib lii lik lil lir liu lkb lkl lkr llb lli llk lll llr llu lrb lri lrk lrr lru lub lui luk lul lur luu rbb rbi rbk rbl rbr rbu rib rii rik ril rir rkb rkk rku rli rll rlr rlu rrb rri rrk rrl rrr rru rub rui ruk rur ruu ubb ubi ubk ubl ubr ubu uib uii uil uir uiu ukb uki ukk ukl ukr uku ulb uli ulk ull ulr ulu ur- urb uri urk url urr uru uur uuu