a-be aaaa aaab aaac aaae aaaf aaal aaba aabb aabc aabl aaca aacb aacc aace aacf aacl aaea aaec aafa aafb aafc aaff aafl aala aalc aale aall abaa abab abac abae abaf abal abb- abba abbb abbe abca abcb abcc abcf abcl abec abee abel abff abla able acaa acab acac acae acba acbl acca accc acce accf ace- acea acec acel acfc acfe acfl acla aclc acle aeac aeaf aecb aecl aela aelc afaa afca afcb afcc afee afel affa affc afla aflc afle alaa alac alae alal alb- alba albc albe alca alcc alce alea alec alee alef alfa alfe all- alla alle alll baaa baaf baal baba babb babe bac- baca bacc bace bael bafc baff bala balc bale balf ball bbbb bbeb bbfc bblb bcaa bcbc bcca bccc bccl bcec bcfc beaf beal beba bebb bebe beca beeb beef beel befa befe beff bela bele bell bfca bffl blaa blab blac blae blea bleb blee blfc caaa caab caac caaf caal caba cabe cabf cac- caca cacc cace caec cafa cafb cafc cafe caff cafl cala calc cale calf call cbac cbal cbbc cbca cbcc cbce cbcl cbea cbec cbee cbef cbfb cbfc cblb cblc ccaa ccab ccac ccaf ccba ccbc ccca cccb cccc cccf cccl ccee ccel ccfa ccfc ccff ccfl ccla cclc ceac ceal ceba cec- ceca cece ceeb ceec ceel cef- cefa cefc cel- cela celc cele celf cell cfaa cfab cfac cfae cfbc cfca cfcb cfcf cfcl cffb clab claf clea clec clee clef e-cl e-la eaaf eaba eaca eacc eaec eafb eala ealc eale ebac ebal ebba ebbc ebcc ebel ebfc ebla ecaa ecac ecal ecbc ecbe ecca eccb eccc ecce eccl ecef ecfa ecfc ecla eeca eeea eeee eefa eefe eefl eele efab efca effa efla el-b elab elac elal elba elbe elca elcb elce elea elec elee elef elfa elfc elfe ella elle faaa faac faba fabe faca facc face faeb fafa fafc fafe faff fala falc fale fall fbla fble fcab fcal fcba fcca fccf feaf feal feba fece feeb feel fefc fefe feff fela fele felf fell ffcc ffee ffff flab flac flae flcl flea flee laaa laac laal laba labe laca lacc lace lacl lael lafb lafc lafe laff lala lale lall lbcc lcac lcbc lcca lccc lcce lcfc leaa leaf leal leba leca lece leea leef leel lefa lefe leff lela lele lell lfca lfcc llcc llef lllc llll