-th a-a a-b a-c a-t aaa aab aac aah aak aao aat ab- aba abb abc abh abk abo abt ac- aca acb acc ach ack aco act aha ahb ahc ahh ahk aho aht aka akb akc akh akk ako aoa aob aoc aoh aok aoo aot at- ata atb atc ath ato att baa bab bac bah bak bao bat bba bbb bbc bbh bbk bbo bbt bca bcb bcc bch bck bco bct bha bhb bhc bhh bhk bho bht bka bkb bkc bkk bko bkt boa bob boc boh bok boo bot bta btb btc bth btk bto btt c-- caa cab cac cah cak cao cat cba cbb cbc cbh cbk cbo cbt cca ccb ccc cch cck cco cct ch- cha chb chc chh chk cho cht cka ckb ckc ckh cko ckt co- coa cob coc coh cok coo cot cta ctb ctc cth ctk cto ctt haa hab hac hah hak hao hat hba hbb hbc hbh hbk hbo hbt hca hcb hcc hch hck hco hct hha hhb hhc hhh hhk hho hht hka hkb hkh hkk hko hkt hoa hob hoc hoh hok hoo hot hta htb htc hth htk hto htt k-t ka- kaa kab kac kah kak kao kat kba kbb kbc kbh kbk kbo kca kcb kcc kch kck kct kha khh khk kho kkb kkc kkh kkk kkt koa kob koc koh kok koo kot kta ktb ktc kth ktk kto ktt oaa oab oac oah oak oao oat ob- oba obb obc obh obk obo obt oc- oca ocb occ och ock oco oct oha ohc ohh oho oht oka okb okc okk oko oo- ooa oob ooc ooh ook ooo oot ot- ota otb otc oth otk oto ott taa tab tac tah tak tao tat tba tbb tbc tbh tbk tbo tbt tca tcb tcc tch tck tco tct th- tha thb thc thh thk tho tht tka tkb tkc tkk tko tkt to- toa tob toc toh tok too tot tta ttb ttc tth ttk tto ttt