a-a a-b aaa aab aad aag aak aao ab- aba abb abd abg abk abo ad- ada adb add adg adk ado ag- aga agb agd agg agk ago aka akb akd akg akk ako aoa aob aod aog aok aoo baa bab bad bag bak bao bba bbb bbd bbg bbk bbo bda bdb bdd bdg bdk bdo bga bgb bgd bgg bgk bgo bka bkb bkg bkk bko boa bob bod bog bok boo daa dab dad dag dak dao dba dbb dbd dbg dbk dbo dda ddb ddd ddg ddk ddo dga dgd dgg dgk dka dkb dkg dkk dko doa dob dod dog dok doo g-d gaa gab gad gag gak gao gba gbd gbg gbk gbo gda gdb gdd gdk gdo gga ggb ggd ggg ggo gka gkb gkd gko goa gob god gog gok goo ka- kaa kab kad kag kak kao kba kbb kbd kbk kbo kda kdb kdg kdk kdo kga kgb kgd kgo kkb kkk koa kob kod kog kok koo oaa oab oad oag oak oao ob- oba obb obd obg obk obo oda odb odd odg odo oga ogd ogg ogo oka okb okd okg okk oko oo- ooa oob ood oog ook ooo