a-a a-b a-c a-t aaa aab aac aak aao aat aau aay ab- aba abb abc abk abo abt abu aby ac- aca acb acc ack aco act acu acy aka akb akc akk ako aku aoa aob aoc aok aoo aot aou at- ata atb atc ato att atu au- aua aub auc auk auo aut ay- aya ayc ayk ayo ayt ayu b-u baa bab bac bak bao bat bau bay bba bbb bbc bbk bbo bbt bbu bby bca bcb bcc bck bco bct bcu bcy bka bkb bkc bkk bko bkt boa bob boc bok boo bot bou boy bta btb btc btk bto btt btu bty bua bub buc buk buo but buu buy by- bya byc byk byo byt byu c-- caa cab cac cak cao cat cau cay cba cbb cbc cbk cbo cbt cbu cby cca ccb ccc cck cco cct ccu cka ckb ckc cko ckt cky co- coa cob coc cok coo cot cou coy cta ctb ctc ctk cto ctt ctu cty cua cub cuc cuk cuo cut cuu cuy cya cyb cyc cyk cyo cyt k-t ka- kaa kab kac kak kao kat kau kay kba kbb kbc kbk kbo kbu kca kcb kcc kck kct kcu kkb kkc kkk kkt kku kky koa kob koc kok koo kot kou koy kta ktb ktc ktk kto ktt ktu kub kuc kuk kut kuu kuy kya kyc kyo kyt kyu oaa oab oac oak oao oat oau ob- oba obb obc obk obo obt obu oby oc- oca ocb occ ock oco oct ocu oka okb okc okk oko oku oo- ooa oob ooc ook ooo oot ot- ota otb otc otk oto ott otu ou- oua ouc ouk ouo out oya oyo taa tab tac tak tao tat tau tay tba tbb tbc tbk tbo tbt tbu tca tcb tcc tck tco tct tcu tka tkb tkc tkk tko tkt tky to- toa tob toc tok too tot tou toy tta ttb ttc ttk tto ttt ttu tty tua tub tuc tuk tuo tut tuu tuy tya tyc tyo tyt ua- uaa uab uac uak uao uat uau uay uba ubb ubc ubk ubo ubt ubu uby uca ucb ucc uck uco uct ucu uka ukb ukc ukk uku uoa uob uoc uok uoo uot uta utb utc utk uto utt utu uty uua uuc uut uuu uyc uyo uyu yaa yab yac yak yao yat yau yay ybc yby yca ycc yco ycu ycy yka ykk yob yoc yok yoo yot you yoy yta ytc ytk yto ytt ytu yua yuk yuo yut yuu yuy yyb yyc yyt yyu yyy