-er c-- ccc cce cck ccn cco ccp ccr ccs ce- cec cee cek cen ceo cep cer ces ckc cko cks cn- cnc cne cnn cno cnp cnr cns co- coc coe cok con coo cop cor cos cpc cpe cpk cpn cpo cpp cpr cps crc cre crk crn cro crp crr crs csc cse csk csn cso csp csr css ec- ecc ece eck ecn eco ecr ecs eec eee eek een eeo eep eer ees ekc eke eko ekp ekr eks en- enc ene enk enn eno enp enr ens eo- eoc eoe eok eon eoo eop eor eos ep- epc epe epn epo epp epr eps erc ere erk ern ero erp err ers es- esc ese esk esn eso esp esr ess kcc kce kck kcn kcp kcr kcs ke- kec kee kek ken keo kep ker kes kkc kke kkk kkn kkp kkr kks kn- knc kne knk knn kno knp knr koc koe kok kon koo kop kor kos kpc kpe kpk kpn kpo kpp kpr kps krc krk krn kro krp krr krs ksc kse ksk ksn kso ksp ksr kss ncc nce nck ncn nco ncp ncr ncs ne- nec nee nek nen neo nep ner nes nkc nke nkk nkn nko nkp nkr nks nnc nne nnk nnn nno nnp nns no- noc noe nok non noo nop nor nos npc npe npn npo npp npr nps nrc nre nrk nrn nro nrp nrr nrs nsc nse nsk nsn nso nsp nsr nss oc- occ ock ocn oco ocp ocr ocs oec oee oen oeo oep oer oes okc oke okk oko okp okr oks on- onc one onk onn ono onp onr ons oo- ooc ook oon ooo oop oor oos op- opc ope opk opn opo opp opr ops or- orc ore ork orn oro orp orr ors os- osc ose osk osn oso osp osr oss p-p pcc pce pck pcn pco pcp pcr pcs pec pee pek pen peo pep per pes pkc pke pkn pko pkp pkr pks pn- pnc pne pnk pnn pno pnp pnr pns poc poe pok pon poo pop por pos ppc ppe ppk ppn ppo ppp ppr pps prc pre prk prn pro prp prr prs ps- psc pse psk psn pso psp psr pss rcc rce rcn rco rcp rcr rcs re- rec ree rek ren reo rep rer res rkc rke rkk rko rkp rks rnc rnn rno rnp rnr rns roc roe rok ron roo rop ror ros rpc rpe rpk rpn rpo rpp rpr rps rrc rrk rrn rrp rrr rrs rsc rse rsk rsn rso rsp rsr rss scc sce sck scn sco scp scr scs se- sec see sek sen seo sep ser ses sk- skc ske skk sko skp skr sks snc sne snk snn sno snp snr sns soc soe sok son soo sop sor sos spc spe spk spn spo spp spr sps sr- src sre srk srn sro srp srr srs ss- ssc sse ssk ssn sso ssp ssr sss