a-a a-b a-c a-t aaa aab aac aad aak aao aat aay ab- aba abb abc abd abk abo abt aby ac- aca acb acc acd ack aco act acy ad- ada adb adc add adk ado adt ady aka akb akc akd akk ako aoa aob aoc aod aok aoo aot at- ata atb atc atd ato att ay- aya ayc ayd ayk ayo ayt baa bab bac bad bak bao bat bay bba bbb bbc bbd bbk bbo bbt bby bca bcb bcc bcd bck bco bct bcy bda bdb bdc bdd bdk bdo bdt bdy bka bkb bkc bkk bko bkt boa bob boc bod bok boo bot boy bta btb btc btd btk bto btt bty by- bya byc byd byk byo byt c-- caa cab cac cad cak cao cat cay cba cbb cbc cbd cbk cbo cbt cby cca ccb ccc ccd cck cco cct cda cdb cdc cdd cdk cdo cdt cdy cka ckb ckc ckd cko ckt cky co- coa cob coc cod cok coo cot coy cta ctb ctc ctd ctk cto ctt cty cya cyb cyc cyd cyk cyo cyt daa dab dac dad dak dao dat day dba dbb dbc dbd dbk dbo dbt dby dca dcb dcc dcd dck dco dct dda ddb ddc ddd ddk ddo ddt ddy dka dkb dkc dkk dko dkt doa dob doc dod dok doo dot doy dta dtb dtc dtd dtk dto dtt dty dy- dya dyb dyc dyd dyk dyo dyy k-t ka- kaa kab kac kad kak kao kat kay kba kbb kbc kbd kbk kbo kca kcb kcc kcd kck kct kda kdb kdc kdk kdo kdt kdy kkb kkc kkk kkt kky koa kob koc kod kok koo kot koy kta ktb ktc ktk kto ktt kya kyc kyd kyo kyt oaa oab oac oad oak oao oat ob- oba obb obc obd obk obo obt oby oc- oca ocb occ ocd ock oco oct oda odb odc odd odo odt oka okb okc okd okk oko oo- ooa oob ooc ood ook ooo oot ot- ota otb otc otd otk oto ott oya oyd oyo taa tab tac tad tak tao tat tay tba tbb tbc tbd tbk tbo tbt tca tcb tcc tcd tck tco tct tda tdb tdc tdd tdk tdo tdt tdy tka tkb tkc tkk tko tkt tky to- toa tob toc tod tok too tot toy tta ttb ttc ttd ttk tto ttt tty tya tyc tyd tyo tyt yaa yab yac yad yak yao yat yay ybc yby yca ycc ycd yco ycy yda ydo ydt ydy yka ykk yob yoc yod yok yoo yot yoy yta ytc ytd ytk yto ytt yyb yyc yyt yyy