-er c-- ccc cce ccf cco ccr ccu ce- cec cee cef ceo cer ceu cfc cfe cff cfo cfr cfu co- coc coe cof coo cor cou crc cre crf cro crr cru cuc cue cuf cuo cur cuu ec- ecc ece ecf eco ecr ecu eec eee eef eeo eer ef- efc efe eff efo efr eo- eoc eoe eof eoo eor eou erc ere erf ero err eru eu- euc eue euf eur fcc fce fcf fco fcr fcu fec fee fef feo fer feu ffc ffe fff ffo ffr ffu foc foe fof foo for fou frc fre frf fro frr fru fue fuf fuo fur fuu oc- occ ocf oco ocr ocu oec oee oef oeo oer of- ofc ofe off ofo ofr ofu oo- ooc oof ooo oor or- orc ore orf oro orr oru ou- ouc oue ouf ouo our rcc rce rcf rco rcr rcu re- rec ree ref reo rer reu rfc rfe rff rfo rfr rfu roc roe rof roo ror rou rrc rrf rrr rru ruc rue ruf ruo rur ruu ucc uce ucf uco ucr ucu uec uee uef uer ufc ufe uff ufo ufr ufu uoc uoe uoo uor ur- urc ure urf uro urr uru uuc uue uur uuu