ddd ddm ddo ddr dds dmd dmm dmo dmr dms dod dom doo dor dos drd drm dro drr drs dsd dsm dso dsr dss m-o m-r mdd mdm mdo mdr mds mmd mmm mmo mmr mms mod mom moo mor mos mrd mrm mro mrr mrs msd msm mso msr mss odd odm odo odr ods om- omd omm omo omr oms oo- ood oom ooo oor oos or- ord orm oro orr ors os- osd osm oso osr oss rdd rdm rdo rdr rds rmd rmm rmo rmr rms rod rom roo ror ros rrd rrm rrr rrs rsd rsm rso rsr rss sdd sdm sdo sdr sds smd smm smo smr sms sod som soo sor sos sr- srd srm sro srr srs ss- ssd ssm sso ssr sss