a-a a-b a-c aaa aab aac aad aak aao aar aas ab- aba abb abc abd abk abo abr abs ac- aca acb acc acd ack aco acr acs ad- ada adb adc add adk ado adr ads aka akb akc akd akk ako akr aks aoa aob aoc aod aok aoo aor aos ar- ara arb arc ard ark aro arr ars as- asa asb asc asd ask aso asr ass baa bab bac bad bak bao bar bas bba bbb bbc bbd bbk bbo bbr bbs bca bcb bcc bcd bck bco bcr bcs bda bdb bdc bdd bdk bdo bdr bds bka bkb bkc bkk bko bkr bks boa bob boc bod bok boo bor bos bra brb brd brk bro brr brs bsa bsb bsc bsd bsk bso bsr bss c-- caa cab cac cad cak cao car cas cba cbb cbc cbd cbk cbo cbr cbs cca ccb ccc ccd cck cco ccr ccs cda cdb cdc cdd cdk cdo cdr cds cka ckb ckc ckd cko cks co- coa cob coc cod cok coo cor cos cra crb crc crd crk cro crr crs csa csb csc csd csk cso csr css daa dab dac dad dak dao dar das dba dbb dbc dbd dbk dbo dbr dbs dca dcb dcc dcd dck dco dcr dcs dda ddb ddc ddd ddk ddo ddr dds dka dkb dkc dkk dko dkr dks doa dob doc dod dok doo dor dos dra drb drc drd drk dro drr drs dsa dsb dsc dsd dsk dso dsr dss ka- kaa kab kac kad kak kao kar kas kba kbb kbc kbd kbk kbo kbr kbs kca kcb kcc kcd kck kcr kcs kda kdb kdc kdk kdo kdr kds kkb kkc kkk kkr kks koa kob koc kod kok koo kor kos kra krc krd krk kro krr krs ksa ksb ksc ksd ksk kso ksr kss oaa oab oac oad oak oao oar oas ob- oba obb obc obd obk obo obr obs oc- oca ocb occ ocd ock oco ocr ocs oda odb odc odd odo odr ods oka okb okc okd okk oko okr oks oo- ooa oob ooc ood ook ooo oor oos or- ora orb orc ord ork oro orr ors os- osa osb osc osd osk oso osr oss ra- raa rab rac rad rak rao rar ras rba rbb rbc rbd rbk rbo rbr rbs rca rcb rcc rcd rco rcr rcs rda rdb rdc rdd rdo rdr rds rkb rkc rkk rko rks roa rob roc rod rok roo ror ros rra rrb rrc rrd rrk rrr rrs rsa rsb rsc rsd rsk rso rsr rss saa sab sac sad sak sao sar sas sba sbb sbc sbd sbk sbo sbr sbs sca scb scc scd sck sco scr scs sda sdb sdc sdd sdk sdo sdr sds sk- ska skb skc skd skk sko skr sks soa sob soc sod sok soo sor sos sr- sra srb src srd srk sro srr srs ss- ssa ssb ssc ssd ssk sso ssr sss

a-ak a-do a-ok aaaa aaab aaac aaad aaar aaas aaba aabb aabc aabd aaca aacb aacc aacd aack aaco aacr aacs aada aadc aads aaka aaoo aara aarc aard aaro aars aasa aasc aasd aass abaa abab abac abad abak abar abas abb- abba abbb abbo abbr abbs abca abcb abcc abcd abcr abcs abda abdo aboa abob abod abok aboo abor abos abra abrc abro abrs abs- absa absd abss acaa acab acac acad acar acas acba acca accc accd acco accs acda acdb acdc acds ackd acks acoa acod acor acos acr- acra acrc acro acrr acrs acsa acsc acsd acss adaa adab adac adad adak adao adar adas adba adbc adcc adcs adda addc addd addo addr adds adob adoc adod adok adoo ador ados adra adro adrs adsa adso adsr adss akaa akao akar akas akca akka akko akok akos akr- akra aksa aoba aoca aocs aoks aora aorb aors aosd aoss arab arac arad arak arar aras arba arbs arc- arca arco arcs arda ardc ardo ards arka arko arks aroa arob arod aroo aror aros arr- arra arrc arrk arro arrr arrs ars- arsa arsc arsd arsk arso asaa asab asac asad asak asao asar asas asba asbo asc- asca ascb ascc asco ascr asda asdo asds aska asko askr asks asob asoc asod asok asor asos asra asrc asro asrs assa assc assd assk asso assr asss baaa baad baak baar baas baba babb babo babr babs bac- baca bacc back baco bacs bada badb badd bado badr bads bak- baka bako bakr baks baos bar- bara barb barc bard bark baro barr bars basa basc bask baso bass bbad bbas bbbb bbbs bbdd bbdo bbrc bcaa bcar bcas bcbc bcbs bcca bccc bccs bcda bcds bcor bcos bcra bcrs bcsa bcsc bcss bd-r bdbc bddc bdos bdsd boab boac boad boak boar boas boba bobb bobo bobs boca bock boco bocs boda bodb bodo bods boka boko boks boob booc bood book boor boos bor- bora bord bork boro borr bors bosa bosc bosk boso boss brab brac brad brak brao bras brca brcb brda brdo brds brka brkb broa brob broc brod brok broo bror bros brrr brrs brsb brsr bsaa bsac bsas bsbd bscs bsod bsos bsra bsrd bssc bssd c-bo c-cd caaa caab caac caas caba cabo cabs cac- caca cacc cack caco cacr cada cadc cadd cado cadr cads caka caod caor caos cara carb carc card cark caro carr cars casa casb casc casd cask caso casr cass cbac cbar cbbc cbbs cbca cbcc cbcr cbcs cbdb cbdc cbdo cbds cbka cbko cbkr cbrd cbsa cbsc ccaa ccab ccac ccad ccar ccas ccba ccbc ccca cccb cccc cccs ccdc ccdr ccds ccob ccoc ccod ccra ccrc ccrs ccsa ccsd ccss cd-r cdaa cdac cdad cdba cdcs cdda cddb cddr cdos cdrs cdss ckac ckbc ckck ckco ckcs ckdo ckoa ckob ckoc ckoo ckor