b-p bbb bbd bbo bbp bbr bbt bdb bdd bdo bdp bdr bdt bob bod boo bop bor bot bpb bpd bpo bpp bpr bpt brb brd bro brp brr brt btb btd bto btp btr btt dbb dbd dbo dbp dbr dbt ddb ddd ddo ddp ddr ddt dob dod doo dop dor dot dpb dpd dpo dpp dpr dpt drb drd dro drp drr drt dtb dtd dto dtp dtr dtt ob- obb obd obo obp obr obt odb odd odo odp odr odt oo- oob ood ooo oop oor oot op- opb opd opo opp opr opt or- orb ord oro orp orr ort ot- otb otd oto otp otr ott p-p pbb pbd pbo pbp pbr pbt pdb pdd pdo pdp pdr pdt pob pod poo pop por pot ppb ppd ppo ppp ppr ppt prb prd pro prp prr prt pt- ptb ptd pto ptp ptr ptt rbb rbd rbo rbp rbr rbt rdb rdd rdo rdp rdr rdt rob rod roo rop ror rot rpb rpd rpo rpp rpr rpt rrb rrd rrp rrr rrt rtb rtd rto rtp rtr rtt tbb tbd tbo tbp tbr tbt tdb tdd tdo tdp tdr tdt to- tob tod too top tor tot tpb tpd tpo tpp tpr tpt trb trd tro trp trr trt ttb ttd tto ttp ttr ttt