b-u bbb bbd bbh bbk bbo bbr bbu bdb bdd bdh bdk bdo bdr bdu bhb bhd bhh bhk bho bhr bhu bkb bkk bko bkr bob bod boh bok boo bor bou brb brd brh brk bro brr bru bub bud buh buk buo bur buu dbb dbd dbh dbk dbo dbr dbu ddb ddd ddh ddk ddo ddr ddu dh- dhb dhd dhh dhk dho dhr dhu dkb dkk dko dkr dku dob dod doh dok doo dor dou drb drd drk dro drr dru dub dud duh duk duo dur hbb hbd hbh hbk hbo hbr hbu hdb hdd hdh hdk hdo hdr hdu hhb hhd hhh hhk hho hhr hhu hkb hkd hkh hkk hko hkr hku hob hod hoh hok hoo hor hou hr- hrb hrd hrh hrk hro hrr hru hub hud huh huk huo hur huu kbb kbd kbh kbk kbo kbr kbu kdb kdh kdk kdo kdr kdu khh khk kho khr khu kkb kkh kkk kkr kku kob kod koh kok koo kor kou krd krk kro krr kru kub kud kuh kuk kur kuu ob- obb obd obh obk obo obr obu odb odd odh odo odr odu ohd ohh oho ohr ohu okb okd okk oko okr oku oo- oob ood ooh ook ooo oor or- orb ord orh ork oro orr oru ou- oud ouh ouk ouo our rbb rbd rbh rbk rbo rbr rbu rdb rdd rdh rdo rdr rdu rh- rhb rhd rhh rho rhr rhu rkb rkk rko rku rob rod roh rok roo ror rou rrb rrd rrh rrk rrr rru rub rud ruh ruk ruo rur ruu ubb ubh ubk ubo ubr ubu udb udd udk udo udr udu uhb uhd uhh uho uhr uhu ukb ukk ukr uku uob uod uok uoo uor ur- urb urd urk uro urr uru uur uuu