-er c-- ccc cce ccn ccp ccr ccs ce- cec cee cen cep cer ces cn- cnc cne cnn cnp cnr cns cpc cpe cpn cpp cpr cps crc cre crn crp crr crs csc cse csn csp csr css ec- ecc ece ecn ecr ecs eec eee een eep eer ees en- enc ene enn enp enr ens ep- epc epe epn epp epr eps erc ere ern erp err ers es- esc ese esn esp esr ess ncc nce ncn ncp ncr ncs ne- nec nee nen nep ner nes nnc nne nnn nnp nns npc npe npn npp npr nps nrc nre nrn nrp nrr nrs nsc nse nsn nsp nsr nss p-p pcc pce pcn pcp pcr pcs pec pee pen pep per pes pn- pnc pne pnn pnp pnr pns ppc ppe ppn ppp ppr pps prc pre prn prp prr prs ps- psc pse psn psp psr pss rcc rce rcn rcp rcr rcs re- rec ree ren rep rer res rnc rnn rnp rnr rns rpc rpe rpn rpp rpr rps rrc rrn rrp rrr rrs rsc rse rsn rsp rsr rss scc sce scn scp scr scs se- sec see sen sep ser ses snc sne snn snp snr sns spc spe spn spp spr sps sr- src sre srn srp srr srs ss- ssc sse ssn ssp ssr sss