c-- ccc ccd cck ccn cco ccv cdc cdd cdk cdn cdo cdv ckc ckd cko cn- cnc cnd cnn cno cnv co- coc cod cok con coo cov cvc cvd cvk cvn cvo cvv dcc dcd dck dcn dco dcv ddc ddd ddk ddn ddo dkc dkk dko dnc dnd dnk dnn dno doc dod dok don doo dov dvc dvd dvk dvn kcc kcd kck kcn kdc kdk kdo kkc kkk kkn kkv kn- knc knd knk knn kno koc kod kok kon koo kvk kvn kvo kvv ncc ncd nck ncn nco ncv ndc ndd ndk ndn ndo ndv nkc nkk nkn nko nnc nnk nnn nno nnv no- noc nod nok non noo nov nvc nvd nvk nvn nvv oc- occ ocd ock ocn oco ocv odc odd odn odo odv okc okd okk oko on- onc ond onk onn ono oo- ooc ood ook oon ooo oov ov- ovc ovd ovo ovv vcc vcd vcn vco vdc vdd vdk vdo vdv vn- vnd vno vnv voc vod vok von voo vov vvc vvo vvv