-er a-a a-b a-c a-t aaa aab aac aae aaf aao aar aat ab- aba abb abc abe abf abo abr abt ac- aca acb acc ace acf aco acr act aea aeb aec aee aef aeo aer aet af- afa afb afc afe aff afo afr aft aoa aob aoc aoe aof aoo aor aot ar- ara arb arc are arf aro arr art at- ata atb atc ate atf ato atr att baa bab bac bae baf bao bar bat bba bbb bbc bbe bbf bbo bbr bbt bca bcb bcc bce bcf bco bcr bct be- bea beb bec bee bef beo ber bet bfa bfb bfc bfe bff bfo bfr bft boa bob boc boe bof boo bor bot bra brb bre brf bro brr brt bta btb btc bte btf bto btr btt c-- caa cab cac cae caf cao car cat cba cbb cbc cbe cbf cbo cbr cbt cca ccb ccc cce ccf cco ccr cct ce- cea ceb cec cee cef ceo cer cet cfa cfb cfc cfe cff cfo cfr cft co- coa cob coc coe cof coo cor cot cra crb crc cre crf cro crr crt cta ctb ctc cte ctf cto ctr ctt eaa eab eac eae eaf eao ear eat eba ebb ebc ebe ebf ebo ebr ebt ec- eca ecb ecc ece ecf eco ecr ect eea eeb eec eee eef eeo eer eet ef- efa efb efc efe eff efo efr eft eo- eoa eob eoc eoe eof eoo eor eot era erb erc ere erf ero err ert eta etb etc ete etf eto etr ett faa fab fac fae faf fao far fat fba fbb fbc fbe fbf fbo fbr fbt fca fcb fcc fce fcf fco fcr fct fea feb fec fee fef feo fer fet ffa ffc ffe fff ffo ffr fft foa fob foc foe fof foo for fot fra frb frc fre frf fro frr frt fta ftb ftc fte ftf fto ftr ftt oaa oab oac oae oaf oao oar oat ob- oba obb obc obe obf obo obr obt oc- oca ocb occ ocf oco ocr oct oea oeb oec oee oef oeo oer oet of- ofa ofb ofc ofe off ofo ofr oft oo- ooa oob ooc oof ooo oor oot or- ora orb orc ore orf oro orr ort ot- ota otb otc ote otf oto otr ott ra- raa rab rac rae raf rao rar rat rba rbb rbc rbe rbf rbo rbr rbt rca rcb rcc rce rcf rco rcr rct re- rea reb rec ree ref reo rer ret rfa rfb rfc rfe rff rfo rfr rft roa rob roc roe rof roo ror rot rra rrb rrc rrf rrr rrt rta rtb rtc rte rtf rto rtr rtt taa tab tac tae taf tao tar tat tba tbb tbc tbe tbf tbo tbr tbt tca tcb tcc tce tcf tco tcr tct te- tea teb tec tee tef teo ter tet tfa tfb tfc tfe tff tfo tfr tft to- toa tob toc toe tof too tor tot tra trb trc tre trf tro trr trt tta ttb ttc tte ttf tto ttr ttt

a-be aaaa aaab aaac aaae aaaf aaar aaba aabb aabc aabt aaca aacb aacc aace aacf aaco aacr aact aaea aaec aafa aafb aafc aaff aaoe aaoo aara aarc aare aaro aart aata aatc aatf aatt abaa abab abac abae abaf abar abat abb- abba abbb abbe abbo abbr abbt abca abcb abcc abcf abcr abct abec abee aber abet abff aboa abob abof aboo abor abot abra abrc abro abta ac-t acaa acab acac acae acar acat acba acca accc acce accf acco acct ace- acea acec acer acet acfc acfe acft acoa acoe acor acot acr- acra acrc acre acro acrr acta actc acte actf acto actt aeac aeaf aecb aect aeer aer- aera aerc aero aeta aetc aetf aeto aetr aett afaa afao afar afat afca afcb afcc afee afer afet affa affc affo afft afoa afoe afoo afor afr- afra afrc afre afro afta aftc afte aoba aoca aoce aora aorb aort aotc aotf arab arac arae araf arar arat arba arbe arc- arca arce arco arct area arec aree aref areo aret arfa arfb arfc arff arft aroa arob aroe aroo aror arr- arra arrc arre arro arrr arrt arta artc arte arto artr at-t ataa atab atac atae atar atat atca atcc atcf atco atcr atea atec atee atef ateo ater atfb atfc atfe atob atoc atoe atof ator atot atra atrc atre atro atta atte atto attr baaa baaf baar baat baba babb babe babo babr bac- baca bacc bace baco bact baer bafc baff bafo baft bar- bara barb barc bare barf baro barr bart bata batc bate batf bato batt bbbb bbeb bbet bbfc bbrc bcaa bcar bcat bcbc bcca bccc bcec bcer bcet bcfc bcof bcor bcra bctc beaf bear beat beba bebb bebe bebo beca beeb beef beer beet befa befe beff befo beft beo- beof beor beot bera berc bere bero berr bert beta betc bete beto bett bfca bfta bftt boab boac boar boat boba bobb bobe bobo boca boce boco boea boec boee boef boeo boer boet bofa bofe boff boob booc booe boof boor boot bor- bora bore borf boro borr bort bota botb bote boto bott brab brac brae braf brao brat brca brcb brce brea breb brec bree bref breo brer bret brfc broa brob broc broe broo bror brot brrr brtc btaa btaf btcc btec btfc btob btor btrc btrt bttb c-bo caaa caab caac caaf caat caba cabe cabf cabo cac- caca cacc cace caco cacr caec caer cafa cafb cafc cafe caff caor cara carb carc care carf caro carr cart cat- cata catb catc cate catf cato catt cbac cbar cbat cbbc cbca cbcc cbce cbcr cbct cbea cbec cbee cbef cber cbet cbfb cbfc cbot cbre cbrt cbta cbtc cbtf ccaa ccab ccac ccaf ccar