c-- ccc ccd cce cck cco ccp cdc cdd cde cdk cdo cdp ce- cec ced cee cek ceo cep ckc ckd cko co- coc cod coe cok coo cop cpc cpd cpe cpk cpo cpp dcc dcd dce dck dco dcp ddc ddd dde ddk ddo ddp de- dec ded dee dek deo dep dkc dke dkk dko dkp doc dod doe dok doo dop dpc dpd dpe dpk dpo dpp ec- ecc ecd ece eck eco ed- edc edd ede edk edo edp eec eed eee eek eeo eep ekc ekd eke eko ekp eo- eoc eod eoe eok eoo eop ep- epc epd epe epo epp kcc kcd kce kck kcp kdc kde kdk kdo kdp ke- kec ked kee kek keo kep kkc kke kkk kkp koc kod koe kok koo kop kpc kpd kpe kpk kpo kpp oc- occ ocd ock oco ocp odc odd ode odo odp oec oed oee oeo oep okc okd oke okk oko okp oo- ooc ood ook ooo oop op- opc opd ope opk opo opp p-p pcc pcd pce pck pco pcp pdc pdd pde pdk pdo pdp pec ped pee pek peo pep pkc pkd pke pko pkp poc pod poe pok poo pop ppc ppd ppe ppk ppo ppp