ddd ddi ddo ddp ddr dds di- did dii dio dip dir dis dod doi doo dop dor dos dpd dpi dpo dpp dpr dps drd dri dro drp drr drs dsd dsi dso dsp dsr dss i-d idd idi ido idp idr ids iid iii iio iip iir iis io- iod ioi ioo iop ior ios ipd ipi ipo ipp ipr ips ir- ird iri iro irp irr irs is- isd isi iso isp isr iss o-i odd odi odo odp odr ods oid oii oio oip oir ois oo- ood ooi ooo oop oor oos op- opd opi opo opp opr ops or- ord ori oro orp orr ors os- osd osi oso osp osr oss p-p pdd pdi pdo pdp pdr pds pid pii pio pip pir pis pod poi poo pop por pos ppd ppi ppo ppp ppr pps prd pri pro prp prr prs ps- psd psi pso psp psr pss rdd rdi rdo rdp rdr rds rid rii rio rip rir ris rod roi roo rop ror ros rpd rpi rpo rpp rpr rps rrd rri rrp rrr rrs rsd rsi rso rsp rsr rss sdd sdi sdo sdp sdr sds sid sii sio sip sir sis sod soi soo sop sor sos spd spi spo spp spr sps sr- srd sri sro srp srr srs ss- ssd ssi sso ssp ssr sss