a-ak aaaa aaab aaac aaal aaba aabb aabc aabl aaca aacb aacc aack aacl aaka aala aalc aall abaa abab abac abaj abak abal abb- abba abbb abca abcb abcc abcl abla ablj acaa acab acac acba acbl acca accc acla aclc ajab ajac ajak ajba ajka ajla akaa akal akca akka alaa alac alak alal alb- alba albc alca alcc alk- alka alkb all- alla alll baaa baak baal baba babb bac- baca bacc back baja bak- baka bakl bala balc balk ball bbbb bblb bcaa bcbc bcca bccc bccl bjcc blaa blab blac blaj blak blkb caaa caab caac caal caba cac- caca cacc cack caja caka cala calc calk call cbac cbal cbbc cbca cbcc cbcl cbka cbkj cbkl cblb cblc ccaa ccab ccac ccba ccbc ccca cccb cccc cccl ccla cclc cjbc cjbk cjca cjcb cjcj cjcl ckac ckbc ckck ckcl clab jaak jaal jaba jaca jacc jack jacl jaja jaka jala jalc jbaa jcbc jccc jjcc jlab kaaa kaab kaak kaal kaba kabb kabc kacb kacc kacl kaja kajb kajc kajk kaka kakc kakj kakk kala kalb kalc kalk kall kbaa kbab kbac kbak kbal kbba kbbb kbbc kbbk kbbl kbca kbcb kbck kbcl kbja kbjc kbjk kbkb kbkk kbkl kbla kblb kblj kbll kcaa kcab kcac kcal kcba kcbc kcbk kcbl kcca kccb kccc kcck kccl kcjb kcjc kcjj kcjk kckc kckj kckk kckl kcla kclc kclk kcll kjaa kjac kjak kjal kjbb kjbl kjcb kjcc kjck kjjj kjjk kjjl kjkj kjkk kjla kjll kkaa kkac kkal kkba kkbb kkbj kkbl kkcb kkcj kkck kkcl kkjb kkjk kkjl kkkj kkkk kklb kklc kkll klaa klab klac klaj klak klal klbb klbc klbj klbl klca klcb klcc klck klcl klja kljb klka klkc klkk klkl klla kllb kllc kllk laaa laac laaj laak laal laba laca lacc lack lacl laja laka lala lall lbcc lcac lcbc lcca lccc ljla lkab lkal llcc lllc llll