c-- ccc ccd cco ccs cdc cdd cdo cds cdy co- coc cod coo cos coy csc csd cso css csy cyc cyd cyo cys dcc dcd dco dcs ddc ddd ddo dds ddy doc dod doo dos doy dsc dsd dso dss dsy dy- dyc dyd dyo dys dyy oc- occ ocd oco ocs odc odd odo ods oo- ooc ood ooo oos os- osc osd oso oss oyd oyo oys scc scd sco scs sdc sdd sdo sds sdy soc sod soo sos soy ss- ssc ssd sso sss sy- syc syd sys ycc ycd yco ycs ycy ydo yds ydy yoc yod yoo yos yoy ysc yso yss ysy yyc yys yyy