-er c-- ccc ccd cce ccf cco ccp ccr ccs cdc cdd cde cdf cdo cdp cdr cds ce- cec ced cee cef ceo cep cer ces cfc cfd cfe cff cfo cfp cfr cfs co- coc cod coe cof coo cop cor cos cpc cpd cpe cpf cpo cpp cpr cps crc crd cre crf cro crp crr crs csc csd cse csf cso csp csr css dcc dcd dce dcf dco dcp dcr dcs ddc ddd dde ddf ddo ddp ddr dds de- dec ded dee def deo dep der des dfc dfd dfe dff dfo dfp dfr dfs doc dod doe dof doo dop dor dos dpc dpd dpe dpf dpo dpp dpr dps drc drd dre dro drp drr drs dsc dsd dse dsf dso dsp dsr dss ec- ecc ecd ece ecf eco ecr ecs ed- edc edd ede edf edo edp edr eds eec eed eee eef eeo eep eer ees ef- efc efd efe eff efo efp efr efs eo- eoc eod eoe eof eoo eop eor eos ep- epc epd epe epf epo epp epr eps erc erd ere erf ero erp err ers es- esc esd ese esf eso esp esr ess fcc fcd fce fcf fco fcp fcr fcs fdc fdd fde fdf fdo fdp fdr fds fec fed fee fef feo fep fer fes ffc ffd ffe fff ffo ffp ffr ffs foc foe fof foo fop for fos fpc fpd fpe fpo fpp fpr fps frc frd fre frf fro frp frr frs fsc fsd fse fsf fso fsp fsr fss oc- occ ocd ocf oco ocp ocr ocs odc odd ode odf odo odp odr ods oec oed oee oef oeo oep oer oes of- ofc ofd ofe off ofo ofp ofr ofs oo- ooc ood oof ooo oop oor oos op- opc opd ope opf opo opp opr ops or- orc ord ore orf oro orp orr ors os- osc osd ose osf oso osp osr oss p-p pcc pcd pce pcf pco pcp pcr pcs pdc pdd pde pdf pdo pdp pdr pds pec ped pee pef peo pep per pes pfc pfd pfe pff pfo pfp pfr pfs poc pod poe pof poo pop por pos ppc ppd ppe ppf ppo ppp ppr pps prc prd pre prf pro prp prr prs ps- psc psd pse psf pso psp psr pss rcc rcd rce rcf rco rcp rcr rcs rdc rdd rde rdf rdo rdp rdr rds re- rec red ree ref reo rep rer res rfc rfd rfe rff rfo rfp rfr rfs roc rod roe rof roo rop ror ros rpc rpd rpe rpf rpo rpp rpr rps rrc rrd rrf rrp rrr rrs rsc rsd rse rsf rso rsp rsr rss scc scd sce scf sco scp scr scs sdc sdd sde sdf sdo sdp sdr sds se- sec sed see sef seo sep ser ses sfc sfd sfe sff sfo sfp sfr sfs soc sod soe sof soo sop sor sos spc spd spe spf spo spp spr sps sr- src srd sre srf sro srp srr srs ss- ssc ssd sse ssf sso ssp ssr sss