-al -ol a-a a-b a-c aaa aab aac aaf aah aak aal aao ab- aba abb abc abf abh abk abl abo ac- aca acb acc acf ach ack acl aco af- afa afb afc aff afh afk afl afo aha ahb ahc ahf ahh ahk ahl aho aka akb akc akh akk akl ako al- ala alb alc alf alh alk all alo aoa aob aoc aof aoh aok aol aoo baa bab bac baf bah bak bal bao bba bbb bbc bbf bbh bbk bbl bbo bca bcb bcc bcf bch bck bcl bco bfa bfb bfc bff bfh bfl bfo bha bhb bhc bhf bhh bhk bhl bho bka bkb bkc bkf bkk bkl bko bla blb blc blf blh blk bll blo boa bob boc bof boh bok bol boo c-- caa cab cac caf cah cak cal cao cba cbb cbc cbf cbh cbk cbl cbo cca ccb ccc ccf cch cck ccl cco cfa cfb cfc cff cfh cfk cfl cfo ch- cha chb chc chf chh chk chl cho cka ckb ckc ckh cko cl- cla clb clc clf clh clk cll clo co- coa cob coc cof coh cok col coo faa fab fac faf fah fak fal fao fba fbb fbc fbf fbh fbk fbl fbo fca fcb fcc fcf fck fcl fco ffa ffc fff ffh ffk ffl ffo fha fhb fhc fhf fhh fhl fho fka fkb fkc fkf fkk fkl fla flb flc flf fll flo foa fob foc fof foh fok fol foo haa hab hac haf hah hak hal hao hba hbb hbc hbf hbh hbk hbl hbo hca hcb hcc hcf hch hck hcl hco hfa hfb hfc hff hfh hfk hfl hfo hha hhb hhc hhf hhh hhk hhl hho hka hkb hkf hkh hkk hkl hko hla hlb hlc hlf hlh hll hlo hoa hob hoc hof hoh hok hol hoo ka- kaa kab kac kaf kah kak kal kao kba kbb kbc kbf kbh kbk kbl kbo kca kcb kcc kch kck kcl kfa kfc kff kfh kfo kha khf khh khk kho kkb kkc kkh kkk kkl kl- kla klb klc klf klh klo koa kob koc kof koh kok kol koo la- laa lab lac laf lah lak lal lao lba lbb lbc lbf lbh lbk lbl lbo lca lcb lcc lcf lch lck lcl lco lfa lfb lfc lff lfh lfk lfl lfo lha lhb lhc lhf lhh lhk lho lka lkb lkh lkl lla llb llc llf llk lll llo loa lob loc lof loh lok lol loo oaa oab oac oaf oah oak oal oao ob- oba obb obc obf obh obk obl obo oc- oca ocb occ ocf och ock ocl oco of- ofa ofb ofc off ofl ofo oha ohc ohf ohh ohl oho oka okb okc okk okl oko ola olb olc olf olk oll olo oo- ooa oob ooc oof ooh ook ool ooo