a-a a-b a-c aaa aab aac aah aak aam aao ab- aba abb abc abh abk abm abo ac- aca acb acc ach ack acm aco aha ahb ahc ahh ahk ahm aho aka akb akc akh akk akm ako ama amb amc amh amk amm amo aoa aob aoc aoh aok aom aoo baa bab bac bah bak bam bao bba bbb bbc bbh bbk bbm bbo bca bcb bcc bch bck bcm bco bha bhb bhc bhh bhk bhm bho bka bkb bkc bkk bkm bko bma bmb bmc bmh bmk bmm bmo boa bob boc boh bok bom boo c-- caa cab cac cah cak cam cao cba cbb cbc cbh cbk cbm cbo cca ccb ccc cch cck ccm cco ch- cha chb chc chh chk chm cho cka ckb ckc ckh ckm cko cma cmb cmc cmh cmk cmm cmo co- coa cob coc coh cok com coo haa hab hac hah hak ham hao hba hbb hbc hbh hbk hbm hbo hca hcb hcc hch hck hcm hco hha hhb hhc hhh hhk hhm hho hka hkb hkh hkk hkm hko hma hmb hmc hmh hmk hmm hmo hoa hob hoc hoh hok hom hoo ka- kaa kab kac kah kak kam kao kba kbb kbc kbh kbk kbm kbo kca kcb kcc kch kck kcm kha khh khk khm kho kkb kkc kkh kkk kkm kma kmb kmc kmh kmk kmm kmo koa kob koc koh kok kom koo m-o maa mab mac mah mak mam mao mba mbb mbc mbh mbk mbm mbo mc- mca mcb mcc mch mck mcm mco mha mhc mhh mhk mhm mho mka mkb mkc mkh mkk mkm mko mma mmb mmc mmh mmk mmm mmo moa mob moc moh mok mom moo oaa oab oac oah oak oam oao ob- oba obb obc obh obk obm obo oc- oca ocb occ och ock ocm oco oha ohc ohh ohm oho oka okb okc okk oko om- oma omb omc omh omm omo oo- ooa oob ooc ooh ook oom ooo