a-a a-b a-c aaa aab aac aad aak aao aar ab- aba abb abc abd abk abo abr ac- aca acb acc acd ack aco acr ad- ada adb adc add adk ado adr aka akb akc akd akk ako akr aoa aob aoc aod aok aoo aor ar- ara arb arc ard ark aro arr baa bab bac bad bak bao bar bba bbb bbc bbd bbk bbo bbr bca bcb bcc bcd bck bco bcr bda bdb bdc bdd bdk bdo bdr bka bkb bkc bkk bko bkr boa bob boc bod bok boo bor bra brb brd brk bro brr c-- caa cab cac cad cak cao car cba cbb cbc cbd cbk cbo cbr cca ccb ccc ccd cck cco ccr cda cdb cdc cdd cdk cdo cdr cka ckb ckc ckd cko co- coa cob coc cod cok coo cor cra crb crc crd crk cro crr daa dab dac dad dak dao dar dba dbb dbc dbd dbk dbo dbr dca dcb dcc dcd dck dco dcr dda ddb ddc ddd ddk ddo ddr dka dkb dkc dkk dko dkr doa dob doc dod dok doo dor dra drb drc drd drk dro drr ka- kaa kab kac kad kak kao kar kba kbb kbc kbd kbk kbo kbr kca kcb kcc kcd kck kcr kda kdb kdc kdk kdo kdr kkb kkc kkk kkr koa kob koc kod kok koo kor kra krc krd krk kro krr oaa oab oac oad oak oao oar ob- oba obb obc obd obk obo obr oc- oca ocb occ ocd ock oco ocr oda odb odc odd odo odr oka okb okc okd okk oko okr oo- ooa oob ooc ood ook ooo oor or- ora orb orc ord ork oro orr ra- raa rab rac rad rak rao rar rba rbb rbc rbd rbk rbo rbr rca rcb rcc rcd rco rcr rda rdb rdc rdd rdo rdr rkb rkc rkk rko roa rob roc rod rok roo ror rra rrb rrc rrd rrk rrr

a-ak a-do a-ok aaaa aaab aaac aaad aaar aaba aabb aabc aabd aaca aacb aacc aacd aack aaco aacr aada aadc aaka aaoo aara aarc aard aaro abaa abab abac abad abak abar abb- abba abbb abbo abbr abca abcb abcc abcd abcr abda abdo aboa abob abod abok aboo abor abra abrc abro acaa acab acac acad acar acba acca accc accd acco acda acdb acdc ackd acoa acod acor acr- acra acrc acro acrr adaa adab adac adad adak adao adar adba adbc adcc adda addc addd addo addr adob adoc adod adok adoo ador adra adro akaa akao akar akca akka akko akok akr- akra aoba aoca aora aorb arab arac arad arak arar arba arc- arca arco arda ardc ardo arka arko aroa arob arod aroo aror arr- arra arrc arrk arro arrr baaa baad baak baar baba babb babo babr bac- baca bacc back baco bada badb badd bado badr bak- baka bako bakr bar- bara barb barc bard bark baro barr bbad bbbb bbdd bbdo bbrc bcaa bcar bcbc bcca bccc bcda bcor bcra bd-r bdbc bddc boab boac boad boak boar boba bobb bobo boca bock boco boda bodb bodo boka boko boob booc bood book boor bor- bora bord bork boro borr brab brac brad brak brao brca brcb brda brdo brka brkb broa brob broc brod brok broo bror brrr c-bo c-cd caaa caab caac caba cabo cac- caca cacc cack caco cacr cada cadc cadd cado cadr caka caod caor cara carb carc card cark caro carr cbac cbar cbbc cbca cbcc cbcr cbdb cbdc cbdo cbka cbko cbkr cbrd ccaa ccab ccac ccad ccar ccba ccbc ccca cccb cccc ccdc ccdr ccob ccoc ccod ccra ccrc cd-r cdaa cdac cdad cdba cdda cddb cddr ckac ckbc ckck ckco ckdo ckoa ckob ckoc ckoo ckor ckrc ckrd coad coak coba cobb cobo coca cock coco coda codd cok- coka coko coob cood cook cor- cora corb corc cord cork coro corr crab crac crar crbc crca crcc crcr crda crdc crkc crob croc crod crok croo cror d-bo daab daad daar daba dabb dabo daca dada dado daka dako dara darb darc dard dark daro darr dbar dbcc dcbc dcca dccb dccc dcdb dcra dcrk dddd ddoc ddrc dkba dkdc doab doak doar doba dobb doca dock doco dod- doda dodd dodo doka doko doob dood dook door dora dorc dord dork doro dorr draa drab drac drad drak drar drba drbc drca drda drob drod drra kaaa kaab kaak kaar kaba kabb kabc kabd kabo kabr kacb kacc kacd kaco kad- kada kadd kado kadr kaka kakc kakk kako kaoa kaoc kaok kaor kara karb kard kark karo karr kbaa kbab kbac kbad kbak kbar kbba kbbb kbbc kbbd kbbk kbbo kbbr kbca kbcb kbck kbco kbcr kbdb kbdo kbdr kbkb kbkk kbko kbkr kboa kbob kboc kbod kbok kboo kbra kbrb kbrc kbrd kbrk kbro kcaa kcab kcac kcad kcar kcba kcbc kcbd kcbk kcbr kcca kccb kccc kccd kcck kccr kcda kcdc kcdd kcdr kckc kckk kcko kckr kcob kcor kcrc kcro kcrr kdaa kdab kdac kdad kdak kdao kdar kdbb kdbr kdca kdcc kdcd kdco kdcr kddb kddc kddd kddk kddr kdka kdkb kdkd kdkk kdko kdkr kdoc kdok kdrb kdro kkaa kkac kkar kkba kkbb kkbd kkbo kkbr kkcb kkcd kkck kkco kkcr kkda kkdc kkdd kkdo kkkk kkoa kkob kkoo kkor kkrb kkrc kkrk kkro kkrr koab koac koak koar koba kobb kobc kobk kobo kobr koca kocb kocd kock koda kodk kodo koka kokb kokc kokk koko kokr koob kooc kook kooo koor kora korb korc kord kork koro korr krab krac krad krak krar krba krbb krbd krbk krbr krca krcb krcc krcd krco krda krdc krdd krdo krdr krka krkc krkd krkk krko krkr kroa krob kroc krod krok kroo kror krrb krrc krrk krro krrr oara obad obak obba obbo obkb obok obor obra obro ocab ocac ocad ocak ocbc