a-a a-b a-c aaa aab aac aad aah aak aao aau ab- aba abb abc abd abh abk abo abu ac- aca acb acc acd ach ack aco acu ad- ada adb adc add adh adk ado adu aha ahb ahc ahd ahh ahk aho ahu aka akb akc akd akh akk ako aku aoa aob aoc aod aoh aok aoo aou au- aua aub auc aud auh auk auo b-u baa bab bac bad bah bak bao bau bba bbb bbc bbd bbh bbk bbo bbu bca bcb bcc bcd bch bck bco bcu bda bdb bdc bdd bdh bdk bdo bdu bha bhb bhc bhd bhh bhk bho bhu bka bkb bkc bkk bko boa bob boc bod boh bok boo bou bua bub buc bud buh buk buo buu c-- caa cab cac cad cah cak cao cau cba cbb cbc cbd cbh cbk cbo cbu cca ccb ccc ccd cch cck cco ccu cda cdb cdc cdd cdh cdk cdo cdu ch- cha chb chc chd chh chk cho chu cka ckb ckc ckd ckh cko co- coa cob coc cod coh cok coo cou cua cub cuc cud cuh cuk cuo cuu daa dab dac dad dah dak dao dau dba dbb dbc dbd dbh dbk dbo dbu dca dcb dcc dcd dck dco dcu dda ddb ddc ddd ddh ddk ddo ddu dh- dha dhb dhc dhd dhh dhk dho dhu dka dkb dkc dkk dko dku doa dob doc dod doh dok doo dou dua dub duc dud duh duk duo haa hab hac had hah hak hao hau hba hbb hbc hbd hbh hbk hbo hbu hca hcb hcc hcd hch hck hco hda hdb hdc hdd hdh hdk hdo hdu hha hhb hhc hhd hhh hhk hho hhu hka hkb hkd hkh hkk hko hku hoa hob hoc hod hoh hok hoo hou hua hub huc hud huh huk huo huu ka- kaa kab kac kad kah kak kao kau kba kbb kbc kbd kbh kbk kbo kbu kca kcb kcc kcd kch kck kcu kda kdb kdc kdh kdk kdo kdu kha khh khk kho khu kkb kkc kkh kkk kku koa kob koc kod koh kok koo kou kub kuc kud kuh kuk kuu oaa oab oac oad oah oak oao oau ob- oba obb obc obd obh obk obo obu oc- oca ocb occ ocd och ock oco ocu oda odb odc odd odh odo odu oha ohc ohd ohh oho ohu oka okb okc okd okk oko oku oo- ooa oob ooc ood ooh ook ooo ou- oua ouc oud ouh ouk ouo ua- uaa uab uac uad uah uak uao uau uba ubb ubc ubh ubk ubo ubu uca ucb ucc ucd uch uck uco ucu uda udb udc udd udk udo udu uha uhb uhc uhd uhh uho uhu uka ukb ukc ukk uku uoa uob uoc uod uok uoo uua uuc uuu