c-- ccc cce cck cco ccs ccv ce- cec cee cek ceo ces cev ckc cko cks co- coc coe cok coo cos cov csc cse csk cso css csv cvc cve cvk cvo cvs cvv ec- ecc ece eck eco ecs ecv eec eee eek eeo ees eev ekc eke eko eks ekv eo- eoc eoe eok eoo eos es- esc ese esk eso ess esv evc eve evo evs evv kcc kce kck kcs ke- kec kee kek keo kes kev kkc kke kkk kks kkv koc koe kok koo kos ksc kse ksk kso kss ksv kvk kvo kvs kvv oc- occ ock oco ocs ocv oec oee oeo oes okc oke okk oko oks oo- ooc ook ooo oos oov os- osc ose osk oso oss osv ov- ovc ove ovo ovs ovv scc sce sck sco scs scv se- sec see sek seo ses sev sk- skc ske skk sko sks soc soe sok soo sos sov ss- ssc sse ssk sso sss ssv svc sve svk svo svs svv v-e vcc vce vco vcs vec vee vek veo ves voc voe vok voo vos vov vsc vse vsk vso vss vsv vvc vvo vvs vvv