a-ak aaaa aaab aaas aaba aabb aabt aaka aasa aass aast aata aatk aatt abaa abab abak abas abat abb- abba abbb abbs abbt abs- absa abss abta abts akaa akas akka aksa akst asaa asab asak asas asat asba aska asks askt assa assk asss asst asta astb asts at-t ataa atab atak atas atat atbs atka atkt atsb atst atta atts baaa baak baas baat baba babb babs bak- baka baks bakt basa bask bass bast bata bats batt bbas bbbb bbbs bsaa bsas bsat bskt bsts btaa btss bttb kaaa kaab kaak kaas kaat kaba kabb kaka kakk kaks kakt kas- kasa kasb kask kass kast kat- kata katb katk kats katt kbaa kbab kbak kbas kbat kbba kbbb kbbk kbbs kbbt kbkb kbkk kbsa kbsb kbsk kbss kbst kbta kbtb kbtk kbts kbtt kkaa kkat kkba kkbb kkbs kkbt kkkk kksa kkss kkst kktk kkts ksab ksak ksas ksat ksba ksbs kska kskb kskk ksks kssa ksss ksst ksta kstb kstk ksts kstt ktaa ktak ktas ktat ktba ktbb ktbt ktkb ktkk ktks ktkt ktsa ktst kttk ktts kttt saab saak saas saat saba sabb sabs saka sakb sakk saks sasa sask sass sast sata satb sats satt sbaa sbas sbbs sbsa sbst sbtk skab skat skss ssaa ssab ssas ssat sssa sssb ssss ssta sstb ssts stab stak stas stat stbs stks stss taa- taas taat taba tabb tabs taka takk taks takt tasa tasb task tass tast tata tatb tats tatt tbas tbbs tbst tbta tkts tsaa tsat tsks tssa tsst tsts ttab ttbb ttss tttt