c-- ccc ccd ccn cco ccr ccs cdc cdd cdn cdo cdr cds cn- cnc cnd cnn cno cnr cns co- coc cod con coo cor cos crc crd crn cro crr crs csc csd csn cso csr css dcc dcd dcn dco dcr dcs ddc ddd ddn ddo ddr dds dnc dnd dnn dno dnr dns doc dod don doo dor dos drc drd drn dro drr drs dsc dsd dsn dso dsr dss ncc ncd ncn nco ncr ncs ndc ndd ndn ndo ndr nds nnc nnn nno nns no- noc nod non noo nor nos nrc nrd nrn nro nrr nrs nsc nsd nsn nso nsr nss oc- occ ocd ocn oco ocr ocs odc odd odn odo odr ods on- onc ond onn ono onr ons oo- ooc ood oon ooo oor oos or- orc ord orn oro orr ors os- osc osd osn oso osr oss rcc rcd rcn rco rcr rcs rdc rdd rdn rdo rdr rds rnc rnd rnn rno rnr rns roc rod ron roo ror ros rrc rrd rrn rrr rrs rsc rsd rsn rso rsr rss scc scd scn sco scr scs sdc sdd sdn sdo sdr sds snc snd snn sno snr sns soc sod son soo sor sos sr- src srd srn sro srr srs ss- ssc ssd ssn sso ssr sss