a-ak aaaa aaab aaac aaad aaas aaba aabb aabc aabd aaca aacb aacc aacd aack aacs aada aadc aads aaka aasa aasc aasd aass abaa abab abac abad abak abas abb- abba abbb abbs abca abcb abcc abcd abcs abda abs- absa absd abss acaa acab acac acad acas acba acca accc accd accs acda acdb acdc acds ackd acks acsa acsc acsd acss adaa adab adac adad adak adas adba adbc adcc adcs adda addc addd adds adsa adss akaa akas akca akka aksa asaa asab asac asad asak asas asba asc- asca ascb ascc asda asds aska asks assa assc assd assk asss baaa baad baak baas baba babb babs bac- baca bacc back bacs bada badb badd bads bak- baka baks basa basc bask bass bbad bbas bbbb bbbs bbdd bcaa bcas bcbc bcbs bcca bccc bccs bcda bcds bcsa bcsc bcss bdbc bddc bdsd bsaa bsac bsas bsbd bscs bssc bssd c-cd caaa caab caac caas caba cabs cac- caca cacc cack cada cadc cadd cads caka casa casb casc casd cask cass cbac cbbc cbbs cbca cbcc cbcs cbdb cbdc cbds cbka cbsa cbsc ccaa ccab ccac ccad ccas ccba ccbc ccca cccb cccc cccs ccdc ccds ccsa ccsd ccss cdaa cdac cdad cdba cdcs cdda cddb cdss ckac ckbc ckck ckcs cksa cksb csaa csab csac csak csas cscb cscc cscd cscs csda csdb cska csks cssa cssd daab daad daas daba dabb dabs daca dacs dada dads daka daks dasa dasb dasc dasd dask dass dbas dbcc dbcs dbsa dbss dcas dcbc dcca dccb dccc dccs dcdb dcds dcsc dcss dddd ddss dkba dkdc dsac dsba dsbc dscc dscs dsda dssa dssc kaaa kaab kaak kaas kaba kabb kabc kabd kacb kacc kacd kacs kad- kada kadd kads kaka kakc kakk kaks kas- kasa kasb kasc kask kass kbaa kbab kbac kbad kbak kbas kbba kbbb kbbc kbbd kbbk kbbs kbca kbcb kbck kbcs kbdb kbds kbkb kbkk kbsa kbsb kbsk kbss kcaa kcab kcac kcad kcas kcba kcbc kcbd kcbk kcbs kcca kccb kccc kccd kcck kcda kcdc kcdd kcds kckc kckk kcsa kcsb kcsc kcsd kcss kdaa kdab kdac kdad kdak kdbb kdbs kdca kdcc kdcd kddb kddc kddd kddk kdka kdkb kdkd kdkk kdsc kdsd kdsk kdss kkaa kkac kkba kkbb kkbd kkbs kkcb kkcd kkck kkcs kkda kkdc kkdd kkkk kksa kksd kkss ksab ksac ksak ksas ksba ksbc ksbs ksca kscb ksck kscs ksdc ksdk ksds kska kskb kskd kskk ksks kssa ksss sa-c saab saac saad saak saas saba sabb sabc sabs saca sacc sacd sack sacs sada sadb sadc sadd sads saka sakb sakk saks sasa sasc sasd sask sass sbaa sbac sbas sbbs sbca sbcc sbcs sbds sbsa sbsd scaa scab scac scad scak scas scba sccc sccs scda scdc scds sck- scsa scsc scsd sdak sdba sdcc sddc sdds sdsc sdss skab skac skad sksd skss ssaa ssab ssac ssas ssca sscc sscs ssdc ssdd sssa sssb sssc ssss