a-ak aaaa aaab aaac aaal aaar aaba aabb aabc aabl aaca aacb aacc aack aacl aacr aaka aala aalc aall aara aarc abaa abab abac abak abal abar abb- abba abbb abbr abca abcb abcc abcl abcr abla abra abrc acaa acab acac acar acba acbl acca accc acla aclc aclr acr- acra acrc acrr akaa akal akar akca akka akr- akra alaa alac alak alal alar alb- alba albc alca alcc alk- alka alkb all- alla alll allr arab arac arak aral arar arba arc- arca arka arla arr- arra arrc arrk arrr baaa baak baal baar baba babb babr bac- baca bacc back bak- baka bakl bakr bala balc balk ball bar- bara barb barc bark barr bbbb bblb bbrc bcaa bcar bcbc bcca bccc bccl bcra blaa blab blac blak blkb blrc brab brac brak brca brcb brka brkb brrr caaa caab caac caal caba cac- caca cacc cack cacr caka cala calc calk call cara carb carc cark carl carr cbac cbal cbar cbbc cbca cbcc cbcl cbcr cbka cbkl cbkr cblb cblc cbrl ccaa ccab ccac ccar ccba ccbc ccca cccb cccc cccl ccla cclc ccra ccrc ccrl ckac ckbc ckck ckcl ckrc clab clar clra crab crac crar crbc crca crcc crcr crkc crkl kaaa kaab kaak kaal kaar kaba kabb kabc kabr kacb kacc kacl kaka kakc kakk kala kalb kalc kalk kall kara karb kark karl karr kbaa kbab kbac kbak kbal kbar kbba kbbb kbbc kbbk kbbl kbbr kbca kbcb kbck kbcl kbcr kbkb kbkk kbkl kbkr kbla kblb kbll kblr kbra kbrb kbrc kbrk kbrl kcaa kcab kcac kcal kcar kcba kcbc kcbk kcbl kcbr kcca kccb kccc kcck kccl kccr kckc kckk kckl kckr kcla kclc kclk kcll kclr kcrc kcrr kkaa kkac kkal kkar kkba kkbb kkbl kkbr kkcb kkck kkcl kkcr kkkk kklb kklc kkll kkrb kkrc kkrk kkrl kkrr klaa klab klac klak klal klar klbb klbc klbl klca klcb klcc klck klcl klcr klka klkc klkk klkl klkr klla kllb kllc kllk klrc klrk klrr krab krac krak kral krar krba krbb krbk krbl krbr krca krcb krcc krcl krka krkc krkk krkr krla krlc krrb krrc krrk krrl krrr laaa laac laak laal laar laba labr laca lacc lack lacl laka lala lall lara larb larc lark larr lbar lbcc lblr lcac lcbc lcca lccc lcra lcrl lkab lkal llcc lllc llll lrac lral lrba lrrc lrrr raab raak raba rabb rabk rabl rac- raca racc rack raka rakk rala ralb rall rara rarb rark rbbb rbbr rbcl rcac rcbc rccb rccc rlab rrrr