c-- ccc cce ccf cck cco ccs ce- cec cee cef cek ceo ces cfc cfe cff cfk cfo cfs ckc cko cks co- coc coe cof cok coo cos csc cse csf csk cso css ec- ecc ece ecf eck eco ecs eec eee eef eek eeo ees ef- efc efe eff efo efs ekc eke ekf eko eks eo- eoc eoe eof eok eoo eos es- esc ese esf esk eso ess fcc fce fcf fck fco fcs fec fee fef fek feo fes ffc ffe fff ffk ffo ffs fkc fkf fkk foc foe fof fok foo fos fsc fse fsf fsk fso fss kcc kce kck kcs ke- kec kee kef kek keo kes kfc kff kfo kfs kkc kke kkk kks koc koe kof kok koo kos ksc kse ksf ksk kso kss oc- occ ocf ock oco ocs oec oee oef oeo oes of- ofc ofe off ofo ofs okc oke okk oko oks oo- ooc oof ook ooo oos os- osc ose osf osk oso oss scc sce scf sck sco scs se- sec see sef sek seo ses sfc sfe sff sfk sfo sfs sk- skc ske skf skk sko sks soc soe sof sok soo sos ss- ssc sse ssf ssk sso sss