-er -ic c-- ccc cce ccf cci cck ccr ce- cec cee cef cei cek cer cfc cfe cff cfi cfk cfr ci- cic cie cif cii cik cir ckc cki crc cre crf cri crk crr ec- ecc ece ecf eci eck ecr eec eee eef eek eer ef- efc efe eff efi efr eic eie eif eii eik eir ekc eke ekf eki ekr erc ere erf eri erk err fcc fce fcf fci fck fcr fec fee fef fei fek fer ffc ffe fff ffi ffk ffr fic fie fif fii fik fir fkc fkf fki fkk frc fre frf fri frk frr i-f icc ice icf ici ick icr ie- iec iee ief iei iek ier ifc ife iff ifi ifr iic iie iif iii iir ikc ike ikf iki ikk ikr ir- irc ire irf iri irk irr kcc kce kci kck kcr ke- kec kee kef kei kek ker kfc kff kfi kic kie kif kii kik kir kkc kke kki kkk kkr krc krf kri krk krr rcc rce rcf rci rcr re- rec ree ref rei rek rer rfc rfe rff rfi rfk rfr ric rie rif rii rik rir rkc rke rkf rkk rrc rrf rri rrk rrr