c-- ccc cce cck cco ccs cct ccv ce- cec cee cek ceo ces cet cev ckc cko cks ckt co- coc coe cok coo cos cot cov csc cse csk cso css cst csv ctc cte ctk cto cts ctt ctv cvc cve cvk cvo cvs cvt cvv ec- ecc ece eck eco ecs ect ecv eec eee eek eeo ees eet eev ekc eke eko eks ekt ekv eo- eoc eoe eok eoo eos eot es- esc ese esk eso ess est esv etc ete etk eto ets ett etv evc eve evo evs evt evv k-t kcc kce kck kcs kct ke- kec kee kek keo kes ket kev kkc kke kkk kks kkt kkv koc koe kok koo kos kot ksc kse ksk kso kss kst ksv ktc kte ktk kto kts ktt ktv kvk kvo kvs kvv oc- occ ock oco ocs oct ocv oec oee oeo oes oet okc oke okk oko oks oo- ooc ook ooo oos oot oov os- osc ose osk oso oss ost osv ot- otc ote otk oto ots ott otv ov- ovc ove ovo ovs ovv scc sce sck sco scs sct scv se- sec see sek seo ses set sev sk- skc ske skk sko sks skt soc soe sok soo sos sot sov ss- ssc sse ssk sso sss sst ssv stc ste stk sto sts stt stv svc sve svk svo svs svt svv tcc tce tck tco tcs tct tcv te- tec tee tek teo tes tet tev tkc tke tkk tko tks tkt to- toc toe tok too tos tot tov tsc tse tsk tso tss tst tsv ttc tte ttk tto tts ttt ttv tvc tve tvk tvo tvs tvt v-e vcc vce vco vcs vct vec vee vek veo ves vet vkt voc voe vok voo vos vot vov vsc vse vsk vso vss vst vsv vtc vte vtk vto vts vtt vtv vvc vvo vvs vvt vvv