a-a a-b aaa aab aad aae aaf aao aas aau ab- aba abb abd abe abf abo abs abu ad- ada adb add ade adf ado ads adu aea aeb aed aee aef aeo aes aeu af- afa afb afd afe aff afo afs afu aoa aob aod aoe aof aoo aos aou as- asa asb asd ase asf aso ass asu au- aua aub aud aue auf auo aus b-u baa bab bad bae baf bao bas bau bba bbb bbd bbe bbf bbo bbs bbu bda bdb bdd bde bdf bdo bds bdu be- bea beb bed bee bef beo bes beu bfa bfb bfd bfe bff bfo bfs bfu boa bob bod boe bof boo bos bou bsa bsb bsd bse bsf bso bss bsu bua bub bud bue buf buo bus buu daa dab dad dae daf dao das dau dba dbb dbd dbe dbf dbo dbs dbu dda ddb ddd dde ddf ddo dds ddu de- dea deb ded dee def deo des deu dfa dfb dfd dfe dff dfo dfs dfu doa dob dod doe dof doo dos dou dsa dsb dsd dse dsf dso dss dsu dua dub dud due duf duo dus eaa eab ead eae eaf eao eas eau eba ebb ebd ebe ebf ebo ebs ebu ed- eda edb edd ede edf edo eds edu eea eeb eed eee eef eeo ees ef- efa efb efd efe eff efo efs eo- eoa eob eod eoe eof eoo eos eou es- esa esb esd ese esf eso ess esu eu- eua eub eud eue euf eus faa fab fad fae faf fao fas fau fba fbb fbd fbe fbf fbo fbs fbu fda fdb fdd fde fdf fdo fds fdu fea feb fed fee fef feo fes feu ffa ffd ffe fff ffo ffs ffu foa fob foe fof foo fos fou fsa fsb fsd fse fsf fso fss fsu fua fub fud fue fuf fuo fus fuu oaa oab oad oae oaf oao oas oau ob- oba obb obd obe obf obo obs obu oda odb odd ode odf odo ods odu oea oeb oed oee oef oeo oes of- ofa ofb ofd ofe off ofo ofs ofu oo- ooa oob ood oof ooo oos os- osa osb osd ose osf oso oss osu ou- oua oud oue ouf ouo ous saa sab sad sae saf sao sas sau sba sbb sbd sbe sbf sbo sbs sbu sda sdb sdd sde sdf sdo sds sdu se- sea seb sed see sef seo ses seu sfa sfb sfd sfe sff sfo sfs sfu soa sob sod soe sof soo sos sou ss- ssa ssb ssd sse ssf sso sss ssu sua sub sud sue suf suo sus suu ua- uaa uab uad uae uaf uao uas uau uba ubb ube ubf ubo ubs ubu uda udb udd ude udf udo uds udu uea ueb ued uee uef ues ufa ufd ufe uff ufo ufs ufu uoa uob uod uoe uoo uos usa usb usd use usf uso uss usu uua uue uus uuu