c-- ccc cce cck ccn cco ccv ce- cec cee cek cen ceo cev ckc cko cn- cnc cne cnn cno cnv co- coc coe cok con coo cov cvc cve cvk cvn cvo cvv ec- ecc ece eck ecn eco ecv eec eee eek een eeo eev ekc eke eko ekv en- enc ene enk enn eno env eo- eoc eoe eok eon eoo evc eve evn evo evv kcc kce kck kcn ke- kec kee kek ken keo kev kkc kke kkk kkn kkv kn- knc kne knk knn kno koc koe kok kon koo kvk kvn kvo kvv ncc nce nck ncn nco ncv ne- nec nee nek nen neo nev nkc nke nkk nkn nko nnc nne nnk nnn nno nnv no- noc noe nok non noo nov nvc nve nvk nvn nvv oc- occ ock ocn oco ocv oec oee oen oeo okc oke okk oko on- onc one onk onn ono oo- ooc ook oon ooo oov ov- ovc ove ovo ovv v-e vcc vce vcn vco vec vee vek ven veo vn- vno vnv voc voe vok von voo vov vvc vvo vvv