-er -ic c-- ccc ccd cce ccf cci cck cco ccr ccs cdc cdd cde cdf cdi cdk cdo cdr cds ce- cec ced cee cef cei cek ceo cer ces cfc cfd cfe cff cfi cfk cfo cfr cfs ci- cic cid cie cif cii cik cio cir cis ckc ckd cki cko cks co- coc cod coe cof coi cok coo cor cos crc crd cre crf cri crk cro crr crs csc csd cse csf csi csk cso csr css dcc dcd dce dcf dci dck dco dcr dcs ddc ddd dde ddf ddi ddk ddo ddr dds de- dec ded dee def dei dek deo der des dfc dfd dfe dff dfi dfk dfo dfr dfs di- dic did die dif dii dik dio dir dis dkc dke dki dkk dko dkr dks doc dod doe dof doi dok doo dor dos drc drd dre dri drk dro drr drs dsc dsd dse dsf dsi dsk dso dsr dss ec- ecc ecd ece ecf eci eck eco ecr ecs ed- edc edd ede edf edi edk edo edr eds eec eed eee eef eek eeo eer ees ef- efc efd efe eff efi efo efr efs eic eid eie eif eii eik eio eir eis ekc ekd eke ekf eki eko ekr eks eo- eoc eod eoe eof eoi eok eoo eor eos erc erd ere erf eri erk ero err ers es- esc esd ese esf esi esk eso esr ess fcc fcd fce fcf fci fck fco fcr fcs fdc fdd fde fdf fdi fdk fdo fdr fds fec fed fee fef fei fek feo fer fes ffc ffd ffe fff ffi ffk ffo ffr ffs fic fid fie fif fii fik fir fis fkc fkf fki fkk foc foe fof foi fok foo for fos frc frd fre frf fri frk fro frr frs fsc fsd fse fsf fsi fsk fso fsr fss i-d i-f icc icd ice icf ici ick ico icr ics idc idd ide idf idi idk ido idr ids ie- iec ied iee ief iei iek ier ies ifc ifd ife iff ifi ifo ifr ifs iic iid iie iif iii iio iir iis ikc ike ikf iki ikk iko ikr iks io- ioc iod ioe iof ioi ioo ior ios ir- irc ird ire irf iri irk iro irr irs is- isc isd ise isf isi isk iso isr iss kcc kcd kce kci kck kcr kcs kdc kde kdf kdk kdo kdr kds ke- kec ked kee kef kei kek keo ker kes kfc kfd kff kfi kfo kfs kic kid kie kif kii kik kio kir kis kkc kke kki kkk kkr kks koc kod koe kof koi kok koo kor kos krc krd krf kri krk kro krr krs ksc ksd kse ksf ksi ksk kso ksr kss o-i oc- occ ocd ocf oci ock oco ocr ocs odc odd ode odf odi odo odr ods oec oed oee oef oei oeo oer oes of- ofc ofd ofe off ofi ofo ofr ofs oic oid oie oif oii oik oio oir ois okc okd oke oki okk oko okr oks oo- ooc ood oof ooi ook ooo oor oos or- orc ord ore orf ori ork oro orr ors os- osc osd ose osf osi osk oso osr oss rcc rcd rce rcf rci rco rcr rcs rdc rdd rde rdf rdi rdo rdr rds re- rec red ree ref rei rek reo rer res rfc rfd rfe rff rfi rfk rfo rfr rfs ric rid rie rif rii rik rio rir ris rkc rke rkf rkk rko rks roc rod roe rof roi rok roo ror ros rrc rrd rrf rri rrk rrr rrs rsc rsd rse rsf rsi rsk rso rsr rss scc scd sce scf sci sck sco scr scs sdc sdd sde sdf sdi sdk sdo sdr sds se- sec sed see sef sei sek seo ser ses sfc sfd sfe sff sfi sfk sfo sfr sfs sic sid sie sif sii sik sio sir sis sk- skc skd ske skf ski skk sko skr sks soc sod soe sof soi sok soo sor sos sr- src srd sre srf sri srk sro srr srs ss- ssc ssd sse ssf ssi ssk sso ssr sss