ddd ddk ddo ddp ddr dds dkk dko dkp dkr dks dod dok doo dop dor dos dpd dpk dpo dpp dpr dps drd drk dro drp drr drs dsd dsk dso dsp dsr dss kdk kdo kdp kdr kds kkk kkp kkr kks kod kok koo kop kor kos kpd kpk kpo kpp kpr kps krd krk kro krp krr krs ksd ksk kso ksp ksr kss odd odo odp odr ods okd okk oko okp okr oks oo- ood ook ooo oop oor oos op- opd opk opo opp opr ops or- ord ork oro orp orr ors os- osd osk oso osp osr oss p-p pdd pdk pdo pdp pdr pds pkd pko pkp pkr pks pod pok poo pop por pos ppd ppk ppo ppp ppr pps prd prk pro prp prr prs ps- psd psk pso psp psr pss rdd rdo rdp rdr rds rkk rko rkp rks rod rok roo rop ror ros rpd rpk rpo rpp rpr rps rrd rrk rrp rrr rrs rsd rsk rso rsp rsr rss sdd sdk sdo sdp sdr sds sk- skd skk sko skp skr sks sod sok soo sop sor sos spd spk spo spp spr sps sr- srd srk sro srp srr srs ss- ssd ssk sso ssp ssr sss