-er c-- ccc cce ccf ccn cco ccr ce- cec cee cef cen ceo cer cfc cfe cff cfn cfo cfr cn- cnc cne cnf cnn cno cnr co- coc coe cof con coo cor crc cre crf crn cro crr ec- ecc ece ecf ecn eco ecr eec eee eef een eeo eer ef- efc efe eff efo efr en- enc ene enf enn eno enr eo- eoc eoe eof eon eoo eor erc ere erf ern ero err fcc fce fcf fcn fco fcr fec fee fef fen feo fer ffc ffe fff ffn ffo ffr fnc fne fnf fnn fnr foc foe fof fon foo for frc fre frf frn fro frr ncc nce ncf ncn nco ncr ne- nec nee nef nen neo ner nfc nfe nff nfn nfo nfr nnc nne nnf nnn nno no- noc noe nof non noo nor nrc nre nrf nrn nro nrr oc- occ ocf ocn oco ocr oec oee oef oen oeo oer of- ofc ofe off ofn ofo ofr on- onc one onf onn ono onr oo- ooc oof oon ooo oor or- orc ore orf orn oro orr rcc rce rcf rcn rco rcr re- rec ree ref ren reo rer rfc rfe rff rfn rfo rfr rnc rnn rno rnr roc roe rof ron roo ror rrc rrf rrn rrr