-er a-a a-b a-c aaa aab aac aae aaf aao aar ab- aba abb abc abe abf abo abr ac- aca acb acc ace acf aco acr aea aeb aec aee aef aeo aer af- afa afb afc afe aff afo afr aoa aob aoc aoe aof aoo aor ar- ara arb arc are arf aro arr baa bab bac bae baf bao bar bba bbb bbc bbe bbf bbo bbr bca bcb bcc bce bcf bco bcr be- bea beb bec bee bef beo ber bfa bfb bfc bfe bff bfo bfr boa bob boc boe bof boo bor bra brb bre brf bro brr c-- caa cab cac cae caf cao car cba cbb cbc cbe cbf cbo cbr cca ccb ccc cce ccf cco ccr ce- cea ceb cec cee cef ceo cer cfa cfb cfc cfe cff cfo cfr co- coa cob coc coe cof coo cor cra crb crc cre crf cro crr eaa eab eac eae eaf eao ear eba ebb ebc ebe ebf ebo ebr ec- eca ecb ecc ece ecf eco ecr eea eeb eec eee eef eeo eer ef- efa efb efc efe eff efo efr eo- eoa eob eoc eoe eof eoo eor era erb erc ere erf ero err faa fab fac fae faf fao far fba fbb fbc fbe fbf fbo fbr fca fcb fcc fce fcf fco fcr fea feb fec fee fef feo fer ffa ffc ffe fff ffo ffr foa fob foc foe fof foo for fra frb frc fre frf fro frr oaa oab oac oae oaf oao oar ob- oba obb obc obe obf obo obr oc- oca ocb occ ocf oco ocr oea oeb oec oee oef oeo oer of- ofa ofb ofc ofe off ofo ofr oo- ooa oob ooc oof ooo oor or- ora orb orc ore orf oro orr ra- raa rab rac rae raf rao rar rba rbb rbc rbe rbf rbo rbr rca rcb rcc rce rcf rco rcr re- rea reb rec ree ref reo rer rfa rfb rfc rfe rff rfo rfr roa rob roc roe rof roo ror rra rrb rrc rrf rrr

a-be aaaa aaab aaac aaae aaaf aaar aaba aabb aabc aaca aacb aacc aace aacf aaco aacr aaea aaec aafa aafb aafc aaff aaoe aaoo aara aarc aare aaro abaa abab abac abae abaf abar abb- abba abbb abbe abbo abbr abca abcb abcc abcf abcr abec abee aber abff aboa abob abof aboo abor abra abrc abro acaa acab acac acae acar acba acca accc acce accf acco ace- acea acec acer acfc acfe acoa acoe acor acr- acra acrc acre acro acrr aeac aeaf aecb aeer aer- aera aerc aero afaa afao afar afca afcb afcc afee afer affa affc affo afoa afoe afoo afor afr- afra afrc afre afro aoba aoca aoce aora aorb arab arac arae araf arar arba arbe arc- arca arce arco area arec aree aref areo arfa arfb arfc arff aroa arob aroe aroo aror arr- arra arrc arre arro arrr baaa baaf baar baba babb babe babo babr bac- baca bacc bace baco baer bafc baff bafo bar- bara barb barc bare barf baro barr bbbb bbeb bbfc bbrc bcaa bcar bcbc bcca bccc bcec bcer bcfc bcof bcor bcra beaf bear beba bebb bebe bebo beca beeb beef beer befa befe beff befo beo- beof beor bera berc bere bero berr bfca boab boac boar boba bobb bobe bobo boca boce boco boea boec boee boef boeo boer bofa bofe boff boob booc booe boof boor bor- bora bore borf boro borr brab brac brae braf brao brca brcb brce brea breb brec bree bref breo brer brfc broa brob broc broe broo bror brrr c-bo caaa caab caac caaf 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 cbac cbar cbbc cbca cbcc cbce cbcr cbea cbec cbee cbef cber cbfb cbfc cbre ccaa ccab ccac ccaf ccar ccba ccbc ccca cccb cccc cccf ccee ccfa ccfc ccff ccob ccoc ccra ccrc ccre ccrf ceac cear ceba cec- ceca cece ceco ceeb ceec cef- cefa cefc ceor cer- cera cerc cere cerf cero cfaa cfab cfac cfae cfao cfar cfbc cfbr cfca cfcb cfcf cfco cffb cffr cfoa cfor cfra cfrb cfre coba cobb cobe cobo coca coce coco cofc cofe coff coob coof cor- cora corb corc core corf coro corr crab crac craf crar crbc crca crcc crce crcr cre- crea creb crec cree creo crfc crob croc croe croo cror eaaf eaba eaca eacc eaec eafb eara earb eare earo ebac ebba ebbc ebbo ebbr ebcc eber ebfc eboe eboo ebor ebro ecaa ecac ecao ecar ecbc ecbe ecca eccb eccc ecce ecco ecef ecfa ecfc ecfr eco- ecra ecrc ecrf ecrr eeca eeea eeee eefa eefe eeoc eera eerc eero efab efbr efca efco efeo effa efor eora eore eraf erba erbb erbe erca ercc erce ereb erec erer erfc erob eroc eroe eroo erra errc erre erro faaa faac faba fabe fabo faca facc face faeb fafa fafc fafe faff fafo fara farb farc fare faro farr fbar fcab fcar fcba fcca fccf fcra feaf fear feba febo fece feeb feer fefc fefe feff fefo feof fera ferb ferc fere fero ferr ffar ffcc ffee ffff ffrr foaf foar foba foca foce foco foer fofo foof for- fora forb fore foro forr frab frac frae frbc frcc frea free freo frfc frob froe o-eo oaer oafc oafo oara oare obba obbo obea obec ober oboe obor obra obre obro ocab ocac ocbc occa occc oce ocee ocef ocfa ocra ocre ocro ocrr oec- oeca oecc oeec oera oere ofcr ofer off- offa offc offe offo offr ofor ofra ofre ooaa ooba oobe oocr ooer ooff oooo oora oore orab orac orae orao orar orba orbb orbe orbo orca orce orco ore- orea oreb orec oreo orer orfe orff oro- oroe