a-a a-b a-i aaa aab aag aai aak aao ab- aba abb abg abi abk abo ag- aga agb agg agi agk ago ai- aia aib aig aii aik aio aka akb akg aki akk ako aoa aob aog aoi aok aoo baa bab bag bai bak bao bba bbb bbg bbi bbk bbo bga bgb bgg bgi bgk bgo bi- bia bib big bii bik bio bka bkb bkg bkk bko boa bob bog boi bok boo gaa gab gag gai gak gao gba gbg gbi gbk gbo gga ggb ggg ggi ggo gia gib gig gii gik gio gka gkb gko goa gob gog goi gok goo ia- iaa iab iag iai iao iba ibb ibg ibi ibk ibo iga igb igg igi igk igo iia iib iii iio ika ikb iki ikk iko io- ioa iob iog ioi ioo ka- kaa kab kag kai kak kao kba kbb kbi kbk kbo kga kgb kgi kgo kia kib kig kii kik kio kkb kki kkk koa kob kog koi kok koo o-i oaa oab oag oai oak oao ob- oba obb obg obi obk obo oga ogg ogi ogo oia oib oii oik oio oka okb okg oki okk oko oo- ooa oob oog ooi ook ooo