a-a a-c aaa aac aad aaf aak aan aao aar ac- aca acc acd acf ack acn aco acr ad- ada adc add adf adk adn ado adr af- afa afc afd aff afk afn afo afr aka akc akd akk akn ako akr an- ana anc and anf ank ann ano anr aoa aoc aod aof aok aon aoo aor ar- ara arc ard arf ark arn aro arr c-- caa cac cad caf cak can cao car cca ccc ccd ccf cck ccn cco ccr cda cdc cdd cdf cdk cdn cdo cdr cfa cfc cfd cff cfk cfn cfo cfr cka ckc ckd cko cn- cna cnc cnd cnf cnn cno cnr co- coa coc cod cof cok con coo cor cra crc crd crf crk crn cro crr daa dac dad daf dak dan dao dar dca dcc dcd dcf dck dcn dco dcr dda ddc ddd ddf ddk ddn ddo ddr dfa dfc dfd dff dfk dfn dfo dfr dka dkc dkk dko dkr dna dnc dnd dnf dnk dnn dno dnr doa doc dod dof dok don doo dor dra drc drd drk drn dro drr faa fac fad faf fak fan fao far fca fcc fcd fcf fck fcn fco fcr fda fdc fdd fdf fdk fdn fdo fdr ffa ffc ffd fff ffk ffn ffo ffr fka fkc fkf fkk fna fnc fnd fnf fnk fnn fnr foa foc fof fok fon foo for fra frc frd frf frk frn fro frr ka- kaa kac kad kaf kak kan kao kar kca kcc kcd kck kcn kcr kda kdc kdf kdk kdo kdr kfa kfc kfd kff kfo kkc kkk kkn kkr kn- kna knc knd knf knk knn kno knr koa koc kod kof kok kon koo kor kra krc krd krf krk krn kro krr naa nac nad naf nak nan nao nar nca ncc ncd ncf nck ncn nco ncr nda ndc ndd ndf ndk ndn ndo ndr nfa nfc nfd nff nfk nfn nfo nfr nka nkc nkf nkk nkn nko nkr nna nnc nnf nnk nnn nno no- noa noc nod nof nok non noo nor nra nrc nrd nrf nrk nrn nro nrr oaa oac oad oaf oak oan oao oar oc- oca occ ocd ocf ock ocn oco ocr oda odc odd odf odn odo odr of- ofa ofc ofd off ofn ofo ofr oka okc okd okk oko okr on- ona onc ond onf onk onn ono onr oo- ooa ooc ood oof ook oon ooo oor or- ora orc ord orf ork orn oro orr ra- raa rac rad raf rak ran rao rar rca rcc rcd rcf rcn rco rcr rda rdc rdd rdf rdn rdo rdr rfa rfc rfd rff rfk rfn rfo rfr rkc rkf rkk rko rna rnc rnd rnn rno rnr roa roc rod rof rok ron roo ror rra rrc rrd rrf rrk rrn rrr