-er c-- ccc cce cck cco ccp ccr ccv ce- cec cee cek ceo cep cer cev ckc cko co- coc coe cok coo cop cor cov cpc cpe cpk cpo cpp cpr cpv crc cre crk cro crp crr crv cvc cve cvk cvo cvp cvr cvv ec- ecc ece eck eco ecr ecv eec eee eek eeo eep eer eev ekc eke eko ekp ekr ekv eo- eoc eoe eok eoo eop eor ep- epc epe epo epp epr erc ere erk ero erp err erv evc eve evo evp evr evv kcc kce kck kcp kcr ke- kec kee kek keo kep ker kev kkc kke kkk kkp kkr kkv koc koe kok koo kop kor kpc kpe kpk kpo kpp kpr kpv krc krk kro krp krr krv kvk kvo kvp kvr kvv oc- occ ock oco ocp ocr ocv oec oee oeo oep oer okc oke okk oko okp okr oo- ooc ook ooo oop oor oov op- opc ope opk opo opp opr opv or- orc ore ork oro orp orr orv ov- ovc ove ovo ovp ovv p-p pcc pce pck pco pcp pcr pcv pec pee pek peo pep per pev pkc pke pko pkp pkr poc poe pok poo pop por pov ppc ppe ppk ppo ppp ppr ppv prc pre prk pro prp prr prv pvc pve pvk pvo pvp pvr pvv rcc rce rco rcp rcr rcv re- rec ree rek reo rep rer rev rkc rke rkk rko rkp rkv roc roe rok roo rop ror rov rpc rpe rpk rpo rpp rpr rpv rrc rrk rrp rrr rvc rve rvo rvp rvr rvv v-e vcc vce vco vcp vcr vec vee vek veo vep ver vkp voc voe vok voo vop vor vov vpc vpe vpk vpo vpp vpr vrc vre vrk vrp vrr vvc vvo vvr vvv