a-ii aaaa aaab aaac aaai aaap aaba aabb aabc aabi aabp aaca aacb aacc aaci aacp aaib aaic aaii aapa aapc aapi abaa abab abac abai abap abb- abba abbb abbi abca abcb abcc abci abcp abia abib abic abpa abpc abpi abpp acaa acab acac acai acap acba acca accc acci accp aci- acia acic acip acpa acpi aiai aiba aica aicc aicp aiia aiib aiic aipa aipi apac apai apap apba apca apcb apcc api- apia apic apip appa appc ba-i baaa baba babb babi bac- baca bacc baci baia baib baic bapa bapc bapi bapp bbbb bbci bcaa bcap bcbc bcbp bcca bccc bcci bcia bcpp biap biba bibb bibi bica bicc bici bipa bipp bpai bpcp caaa caab caac caap caba cabi cac- caca cacc caci caia caib caic caip capa capb capc capi capp cbac cbbc cbca cbcc cbcp cbia cbpc cbpp ccaa ccab ccac ccai ccap ccba ccbc ccca cccb cccc ccci cccp ccic ccii ccip ccpa ccpp ciaa ciba cibc cibi cica cicc cici ciia ciii cipa cipp cpaa cpac cpap cpbc cpca cpia cpic cppa iaaa iaac iaai iaap iaba iaca iacc iacp iaia iapa iapp ibac ibca ibia icaa icab icac icai icap icbc icbp icca iccb iccc icci iccp icpa icpc iiac iica iiii iipa ipac ipba ipca ipcc ippa ippc paap paba paca paci paia paib paip papa papb papi papp pbac pbcc pbpa pcaa pcap pcba pcbc pcca pccc pcia pcip pcpb pcpp piai pibb pibi pica picc pici piia piip pipa pipi pipp ppac ppap ppcc ppci ppib ppic pppa pppp