a-ak a-be aaaa aaab aaac aaad aaae aaaf aaba aabb aabc aabd aaca aacb aacc aacd aace aacf aack aada aadc aade aaea aaec aafa aafb aafc aafd aaff aaka aake abaa abab abac abad abae abaf abak abb- abba abbb abbe abca abcb abcc abcd abcf abda abec abed abee abff acaa acab acac acad acae acba acca accc accd acce accf acda acdb acdc acde acdf ace- acea acec aced acek acfc acfd acfe ackd acke adaa adab adac adad adae adak adba adbc adcc adda addc addd adde adea adeb adee adfa adfc aeac aeaf aecb aede aeka afaa afad afak afca afcb afcc afdb afdc afee afek affa affc afka akaa akae akca aked akee akka baaa baad baaf baak baba babb babe bac- baca bacc bace back bada badb badd bade baed baek bafc baff bak- baka bake bbad bbbb bbdd bbeb bbfc bcaa bcbc bcca bccc bcda bcde bcec bcfc bdbc bddc bead beaf beak beba bebb bebe beca beck beda bede beeb beed beef beek befa befe beff beka beke bfca c-cd caaa caab caac caaf caba cabe cabf cac- caca cacc cace cack cada cadc cadd cade caec cafa cafb cafc cafe caff caka cake cbac cbbc cbca cbcc cbce cbdb cbdc cbea cbec cbee cbef cbfb cbfc cbka ccaa ccab ccac ccad ccaf ccba ccbc ccca cccb cccc cccf ccdc ccdf cced ccee ccfa ccfc ccfd ccff cd-e cdaa cdac cdad cdba cdbf cdda cddb cdec cdef cdfa cdfe ceac cead ceba cec- ceca cece ceda cedd cede ceeb ceec cef- cefa cefc ceke cfaa cfab cfac cfae cfbc cfca cfcb cfcf cfda cffb ckac ckbc ckbe ckck daab daad daae daba dabb daca dace dada dade daeb dafa dafc dafe daff daka dake dbcc dbfc dcbc dcca dccb dccc dcdb dcfc dddd deac dead deae deaf deak deba debe dec- deca decc decd dece deck deda dedd dede deeb deed deef deek defe deff dek- deka deke dfaf dfcc dffa dkba dkdc eaaf eaba eaca eacc eada eadb eadd eaec eafb ebac ebba ebbc ebcc ebed ebfc ecaa ecac ecad ecbc ecbe ecca eccb eccc ecce ecdc ecdf eced ecef ecfa ecfc ecka edac edad edca edda eddc edde ede- edea edfa eeca eede eeea eeee eefa eefe eeka eeke efab efca efda effa efke eka- ekab ekeb eked ekek ekfc ekka f--k faaa faac faad faba fabd fabe faca facc face fack fada fadd fade faeb fafa fafc fafe faff fake fcab fcba fcca fccf fcda fdca fead feaf feak feba fece feck feda fede feeb feed feek fefc fefe feff feke ffcc ffee ffff fkab kaaa kaab kaaf kaak kaba kabb kabc kabd kabe kabf kacb kacc kacd kace kad- kada kadd kade kadf kafa kafc kafe kaff kaka kakc kake kakk kbaa kbab kbac kbad kbae kbak kbba kbbb kbbc kbbd kbbe kbbf kbbk kbca kbcb kbce kbck kbdb kbde kbdf kbeb kbec kbed kbee kbef kbek kbfb kbfc kbff kbfk kbkb kbkf kbkk kcaa kcab kcac kcad kcba kcbc kcbd kcbf kcbk kcca kccb kccc kccd kcck kcda kcdc kcdd kcea kceb kcec kced kcee kcfa kcfb kcfc kcfd kckc kckf kckk kdaa kdab kdac kdad kdae kdaf kdak kdbb kdca kdcc kdcd kdce kddb kddc kddd kddf kddk kdeb kdec kdef kdfc kdka kdkb kdkd kdkk kea- kead keak keba kebb kebc kebe keca keck keda kedb kedc kedd kede keed keef keek kefa kefb kefc keff keka kekb kekc keke kfab kfac kfbc kfbk kfcd kfcf kfda kfeb kfed kffa kffb kfff kffk kfka kfkb kkaa kkac kkba kkbb kkbd kkbe kkcb kkcd kkck kkda kkdc kkdd kkea kked kkkk