c-- ccc ccd ccf ccn cco ccr ccs cdc cdd cdf cdn cdo cdr cds cfc cfd cff cfn cfo cfr cfs cn- cnc cnd cnf cnn cno cnr cns co- coc cod cof con coo cor cos crc crd crf crn cro crr crs csc csd csf csn cso csr css dcc dcd dcf dcn dco dcr dcs ddc ddd ddf ddn ddo ddr dds dfc dfd dff dfn dfo dfr dfs dnc dnd dnf dnn dno dnr dns doc dod dof don doo dor dos drc drd drn dro drr drs dsc dsd dsf dsn dso dsr dss fcc fcd fcf fcn fco fcr fcs fdc fdd fdf fdn fdo fdr fds ffc ffd fff ffn ffo ffr ffs fnc fnd fnf fnn fnr fns foc fof fon foo for fos frc frd frf frn fro frr frs fsc fsd fsf fsn fso fsr fss ncc ncd ncf ncn nco ncr ncs ndc ndd ndf ndn ndo ndr nds nfc nfd nff nfn nfo nfr nfs nnc nnf nnn nno nns no- noc nod nof non noo nor nos nrc nrd nrf nrn nro nrr nrs nsc nsd nsf nsn nso nsr nss oc- occ ocd ocf ocn oco ocr ocs odc odd odf odn odo odr ods of- ofc ofd off ofn ofo ofr ofs on- onc ond onf onn ono onr ons oo- ooc ood oof oon ooo oor oos or- orc ord orf orn oro orr ors os- osc osd osf osn oso osr oss rcc rcd rcf rcn rco rcr rcs rdc rdd rdf rdn rdo rdr rds rfc rfd rff rfn rfo rfr rfs rnc rnd rnn rno rnr rns roc rod rof ron roo ror ros rrc rrd rrf rrn rrr rrs rsc rsd rsf rsn rso rsr rss scc scd scf scn sco scr scs sdc sdd sdf sdn sdo sdr sds sfc sfd sff sfn sfo sfr sfs snc snd snf snn sno snr sns soc sod sof son soo sor sos sr- src srd srf srn sro srr srs ss- ssc ssd ssf ssn sso ssr sss