c-- ccc ccd ccf ccn cco ccr cdc cdd cdf cdn cdo cdr cfc cfd cff cfn cfo cfr cn- cnc cnd cnf cnn cno cnr co- coc cod cof con coo cor crc crd crf crn cro crr dcc dcd dcf dcn dco dcr ddc ddd ddf ddn ddo ddr dfc dfd dff dfn dfo dfr dnc dnd dnf dnn dno dnr doc dod dof don doo dor drc drd drn dro drr fcc fcd fcf fcn fco fcr fdc fdd fdf fdn fdo fdr ffc ffd fff ffn ffo ffr fnc fnd fnf fnn fnr foc fof fon foo for frc frd frf frn fro frr ncc ncd ncf ncn nco ncr ndc ndd ndf ndn ndo ndr nfc nfd nff nfn nfo nfr nnc nnf nnn nno no- noc nod nof non noo nor nrc nrd nrf nrn nro nrr oc- occ ocd ocf ocn oco ocr odc odd odf odn odo odr of- ofc ofd off ofn ofo ofr on- onc ond onf onn ono onr oo- ooc ood oof oon ooo oor or- orc ord orf orn oro orr rcc rcd rcf rcn rco rcr rdc rdd rdf rdn rdo rdr rfc rfd rff rfn rfo rfr rnc rnd rnn rno rnr roc rod rof ron roo ror rrc rrd rrf rrn rrr