-er c-- ccc cce cck ccp ccr ce- cec cee cek cep cer ckc cpc cpe cpk cpp cpr crc cre crk crp crr ec- ecc ece eck ecr eec eee eek eep eer ekc eke ekp ekr ep- epc epe epp epr erc ere erk erp err kcc kce kck kcp kcr ke- kec kee kek kep ker kkc kke kkk kkp kkr kpc kpe kpk kpp kpr krc krk krp krr p-p pcc pce pck pcp pcr pec pee pek pep per pkc pke pkp pkr ppc ppe ppk ppp ppr prc pre prk prp prr rcc rce rcp rcr re- rec ree rek rep rer rkc rke rkk rkp rpc rpe rpk rpp rpr rrc rrk rrp rrr