-er a-a a-b a-c aaa aab aac aad aae aaf aak aan aar aau ab- aba abb abc abd abe abf abk abn abr abu ac- aca acb acc acd ace acf ack acn acr acu ad- ada adb adc add ade adf adk adn adr adu aea aeb aec aed aee aef aek aen aer aeu af- afa afb afc afd afe aff afk afn afr afu aka akb akc akd ake akk akn akr aku an- ana anb anc and ane anf ank ann anr anu ar- ara arb arc ard are arf ark arn arr aru au- aua aub auc aud aue auf auk aun aur b-u baa bab bac bad bae baf bak ban bar bau bba bbb bbc bbd bbe bbf bbk bbn bbr bbu bca bcb bcc bcd bce bcf bck bcn bcr bcu bda bdb bdc bdd bde bdf bdk bdr bdu be- bea beb bec bed bee bef bek ben ber beu bfa bfb bfc bfd bfe bff bfn bfr bfu bka bkb bkc bke bkf bkk bkn bkr bna bnb bnc bnd bne bnf bnk bnn bnr bnu bra brb brd bre brf brk brn brr bru bua bub buc bud bue buf buk bun bur buu c-- caa cab cac cad cae caf cak can car cau cba cbb cbc cbd cbe cbf cbk cbn cbr cbu cca ccb ccc ccd cce ccf cck ccn ccr ccu cda cdb cdc cdd cde cdf cdk cdn cdr cdu ce- cea ceb cec ced cee cef cek cen cer ceu cfa cfb cfc cfd cfe cff cfk cfn cfr cfu cka ckb ckc ckd cn- cna cnb cnc cnd cne cnf cnn cnr cnu cra crb crc crd cre crf crk crn crr cru cua cub cuc cud cue cuf cuk cun cur cuu daa dab dac dad dae daf dak dan dar dau dba dbb dbc dbd dbe dbf dbk dbn dbr dbu dca dcb dcc dcd dce dcf dck dcn dcr dcu dda ddb ddc ddd dde ddf ddk ddn ddr ddu de- dea deb dec ded dee def dek den der deu dfa dfb dfc dfd dfe dff dfk dfn dfr dfu dka dkb dkc dke dkk dkr dku dna dnb dnc dnd dne dnf dnk dnn dnr dra drb drc drd dre drk drn drr dru dua dub duc dud due duf duk dun dur eaa eab eac ead eae eaf eak ean ear eau eba ebb ebc ebd ebe ebf ebk ebn ebr ebu ec- eca ecb ecc ecd ece ecf eck ecn ecr ecu ed- eda edb edc edd ede edf edk edn edr edu eea eeb eec eed eee eef eek een eer ef- efa efb efc efd efe eff efr eka ekb ekc ekd eke ekf ekr eku en- ena enb enc end ene enf enk enn enr enu era erb erc erd ere erf erk ern err eru eu- eua eub euc eud eue euf eun eur faa fab fac fad fae faf fak fan far fau fba fbb fbc fbd fbe fbf fbk fbn fbr fbu fca fcb fcc fcd fce fcf fck fcn fcr fcu fda fdb fdc fdd fde fdf fdk fdn fdr fdu fea feb fec fed fee fef fek fen fer feu ffa ffc ffd ffe fff ffk ffn ffr ffu fka fkb fkc fkf fkk fna fnb fnc fnd fne fnf fnk fnn fnr fnu fra frb frc frd fre frf frk frn frr fru fua fub fud fue fuf fuk fun fur fuu ka- kaa kab kac kad kae kaf kak kan kar kau kba kbb kbc kbd kbe kbf kbk kbn kbr kbu kca kcb kcc kcd kce kck kcn kcr kcu kda kdb kdc kde kdf kdk kdr kdu ke- kea keb kec ked kee kef kek ken ker kfa kfc kfd kff kfu kkb kkc kke kkk kkn kkr kku kn- kna knc knd kne knf knk knn knr knu kra krc krd krf krk krn krr kru kub kuc kud kue kuk kun kur kuu naa nab nac nad nae naf nak nan nar nau nba nbb nbc nbd nbe nbf nbk nbn nbr nbu nca ncb ncc ncd nce ncf nck ncn ncr ncu nda ndb ndc ndd nde ndf ndk ndn ndr ndu ne- nea neb nec ned nee nef nek nen ner neu nfa nfb nfc nfd nfe nff nfk nfn nfr nfu nka nkc nke nkf nkk nkn nkr nku nna nnb nnc nne nnf nnk nnn nnu nra nrb nrc nrd nre nrf nrk nrn nrr nru nua nub nuc nud nue nuk nun nur nuu ra- raa rab rac rad rae raf rak ran rar rau rba rbb rbc rbd rbe rbf rbk rbn rbr rbu rca rcb rcc rcd rce rcf rcn rcr rcu rda rdb rdc rdd rde rdf rdn rdr rdu re- rea reb rec red ree ref rek ren rer reu rfa rfb rfc rfd rfe rff rfk rfn rfr rfu rkb rkc rke rkf rkk rku rna rnb rnc rnd rnn rnr rnu rra rrb rrc rrd rrf rrk rrn rrr rru rua rub ruc rud rue ruf ruk run rur ruu ua- uaa uab uac uad uae uaf uak uan uar uau uba ubb ubc ube ubf ubk ubn ubr ubu uca ucb ucc ucd uce ucf uck ucn ucr ucu uda udb udc udd ude udf udk udn udr udu uea ueb uec ued uee uef uen uer ufa ufc ufd ufe uff ufn ufr ufu uka ukb ukc uke ukf ukk ukn ukr uku un- una unb unc und une unf unk unn unr unu ur- ura urb urc urd ure urf urk urn urr uru uua uuc uue uun uur uuu