a-be a-ii aaaa aaab aaac aaae aaaf aaai aaba aabb aabc aabi aaca aacb aacc aace aacf aaci aaea aaec aafa aafb aafc aaff aafi aaib aaic aaii abaa abab abac abae abaf abai abb- abba abbb abbe abbi abca abcb abcc abcf abci abec abee abff abia abib abic abie acaa acab acac acae acai acba acca accc acce accf acci ace- acea acec acfc acfe acfi aci- acia acic acie acif aeac aeaf aebi aecb aeci afaa afca afcb afcc afci afee affa affc affi afia afib afif aiai aiba aica aicc aice aicf aiea aiee aiff aiia aiib aiic ba-i baaa baaf baba babb babe babi bac- baca bacc bace baci bafc baff baia baib baic baie bbbb bbci bbeb bbfc bcaa bcbc bcca bccc bcci bcec bcfc bcia bcie beaf beba bebb bebe bebi beca beci beeb beef befa befe beff beia beic bfca biaf biba bibb bibe bibi bica bicc bice bici bieb bief bifa biff bifi caaa caab caac caaf caba cabe cabf cabi cac- caca cacc cace caci caec caei cafa cafb cafc cafe caff caia caib caic cbac cbbc cbca cbcc cbce cbea cbec cbee cbef cbfb cbfc cbia ccaa ccab ccac ccaf ccai ccba ccbc ccca cccb cccc cccf ccci ccee ccfa ccfc ccff ccfi ccic ccii ceac ceba cec- ceca cece ceci ceeb ceec cef- cefa cefc cfaa cfab cfac cfae cfbc cfca cfcb cfcf cffb cfia ciaa ciba cibc cibe cibi cica cicc cici ciee cifa cife ciff ciia ciii eaaf eaba eaca eacc eaec eafb eaif ebac ebba ebbc ebcc ebfc ebic ecaa ecac ecai ecbc ecbe ecca eccb eccc ecce ecci ecef ecfa ecfc ecib eeca eeea eeee eefa eefe efab efca effa effi efic eica eiec eiei faaa faac faba fabe fabi faca facc face faeb fafa fafc fafe faff fafi faie fcab fcba fcca fccf fcic fcii feaf feba fece feeb fefc fefe feff fefi feia feie ffcc ffee ffff ffii fiaa fiac fiaf fiba fibe fica ficc fice fiec fief fifa fifc fife fiff fifi fiii i-be iaaa iaac iaai iaba iaca iacc iaea iaec iafc iafe iaff iaia ibac ibca ibea ibec ibfi ibia ibie icaa icab icac icaf icai icbc icca iccb iccc iccf icci icea icec icee icef icfb ieac iecc ieie ifaa ifac ifae ifbb ific iiac iica iifa iiie iiii