a-a a-b a-c aaa aab aac aah aak aao aau ab- aba abb abc abh abk abo abu ac- aca acb acc ach ack aco acu aha ahb ahc ahh ahk aho ahu aka akb akc akh akk ako aku aoa aob aoc aoh aok aoo aou au- aua aub auc auh auk auo b-u baa bab bac bah bak bao bau bba bbb bbc bbh bbk bbo bbu bca bcb bcc bch bck bco bcu bha bhb bhc bhh bhk bho bhu bka bkb bkc bkk bko boa bob boc boh bok boo bou bua bub buc buh buk buo buu c-- caa cab cac cah cak cao cau cba cbb cbc cbh cbk cbo cbu cca ccb ccc cch cck cco ccu ch- cha chb chc chh chk cho chu cka ckb ckc ckh cko co- coa cob coc coh cok coo cou cua cub cuc cuh cuk cuo cuu haa hab hac hah hak hao hau hba hbb hbc hbh hbk hbo hbu hca hcb hcc hch hck hco hha hhb hhc hhh hhk hho hhu hka hkb hkh hkk hko hku hoa hob hoc hoh hok hoo hou hua hub huc huh huk huo huu ka- kaa kab kac kah kak kao kau kba kbb kbc kbh kbk kbo kbu kca kcb kcc kch kck kcu kha khh khk kho khu kkb kkc kkh kkk kku koa kob koc koh kok koo kou kub kuc kuh kuk kuu oaa oab oac oah oak oao oau ob- oba obb obc obh obk obo obu oc- oca ocb occ och ock oco ocu oha ohc ohh oho ohu oka okb okc okk oko oku oo- ooa oob ooc ooh ook ooo ou- oua ouc ouh ouk ouo ua- uaa uab uac uah uak uao uau uba ubb ubc ubh ubk ubo ubu uca ucb ucc uch uck uco ucu uha uhb uhc uhh uho uhu uka ukb ukc ukk uku uoa uob uoc uok uoo uua uuc uuu