-er c-- ccc cce ccm ccp ccr ce- cec cee cem cep cer cmc cme cmm cmp cmr cpc cpe cpm cpp cpr crc cre crm crp crr ec- ecc ece ecm ecr eec eee eem eep eer em- emc eme emm emp emr ep- epc epe epm epp epr erc ere erm erp err m-r mc- mcc mce mcm mcp mcr mec mee mem mep mer mmc mme mmm mmp mmr mpc mpe mpm mpp mpr mrc mre mrm mrp mrr p-p pcc pce pcm pcp pcr pec pee pem pep per pmc pme pmm pmp pmr ppc ppe ppm ppp ppr prc pre prm prp prr rcc rce rcm rcp rcr re- rec ree rem rep rer rmc rme rmm rmp rmr rpc rpe rpm rpp rpr rrc rrm rrp rrr