c-- ccc ccd ccm cco ccs cdc cdd cdm cdo cds cmc cmd cmm cmo cms co- coc cod com coo cos csc csd csm cso css dcc dcd dcm dco dcs ddc ddd ddm ddo dds dmc dmd dmm dmo dms doc dod dom doo dos dsc dsd dsm dso dss m-o mc- mcc mcd mcm mco mcs mdc mdd mdm mdo mds mmc mmd mmm mmo mms moc mod mom moo mos msc msd msm mso mss oc- occ ocd ocm oco ocs odc odd odm odo ods om- omc omd omm omo oms oo- ooc ood oom ooo oos os- osc osd osm oso oss scc scd scm sco scs sdc sdd sdm sdo sds smc smd smm smo sms soc sod som soo sos ss- ssc ssd ssm sso sss