a-a a-b aaa aab aad aao aar aas aau ab- aba abb abd abo abr abs abu ad- ada adb add ado adr ads adu aoa aob aod aoo aor aos aou ar- ara arb ard aro arr ars aru as- asa asb asd aso asr ass asu au- aua aub aud auo aur aus b-u baa bab bad bao bar bas bau bba bbb bbd bbo bbr bbs bbu bda bdb bdd bdo bdr bds bdu boa bob bod boo bor bos bou bra brb brd bro brr brs bru bsa bsb bsd bso bsr bss bsu bua bub bud buo bur bus buu daa dab dad dao dar das dau dba dbb dbd dbo dbr dbs dbu dda ddb ddd ddo ddr dds ddu doa dob dod doo dor dos dou dra drb drd dro drr drs dru dsa dsb dsd dso dsr dss dsu dua dub dud duo dur dus oaa oab oad oao oar oas oau ob- oba obb obd obo obr obs obu oda odb odd odo odr ods odu oo- ooa oob ood ooo oor oos or- ora orb ord oro orr ors oru os- osa osb osd oso osr oss osu ou- oua oud ouo our ous ra- raa rab rad rao rar ras rau rba rbb rbd rbo rbr rbs rbu rda rdb rdd rdo rdr rds rdu roa rob rod roo ror ros rou rra rrb rrd rrr rrs rru rsa rsb rsd rso rsr rss rsu rua rub rud ruo rur rus ruu saa sab sad sao sar sas sau sba sbb sbd sbo sbr sbs sbu sda sdb sdd sdo sdr sds sdu soa sob sod soo sor sos sou sr- sra srb srd sro srr srs ss- ssa ssb ssd sso ssr sss ssu sua sub sud suo sur sus suu ua- uaa uab uad uao uar uas uau uba ubb ubo ubr ubs ubu uda udb udd udo udr uds udu uoa uob uod uoo uor uos ur- ura urb urd uro urr urs uru usa usb usd uso usr uss usu uua uur uus uuu