c-- ccc ccd cce ccn cco ccp cdc cdd cde cdn cdo cdp ce- cec ced cee cen ceo cep cn- cnc cnd cne cnn cno cnp co- coc cod coe con coo cop cpc cpd cpe cpn cpo cpp dcc dcd dce dcn dco dcp ddc ddd dde ddn ddo ddp de- dec ded dee den deo dep dnc dnd dne dnn dno dnp doc dod doe don doo dop dpc dpd dpe dpn dpo dpp ec- ecc ecd ece ecn eco ed- edc edd ede edn edo edp eec eed eee een eeo eep en- enc end ene enn eno enp eo- eoc eod eoe eon eoo eop ep- epc epd epe epn epo epp ncc ncd nce ncn nco ncp ndc ndd nde ndn ndo ndp ne- nec ned nee nen neo nep nnc nne nnn nno nnp no- noc nod noe non noo nop npc npd npe npn npo npp oc- occ ocd ocn oco ocp odc odd ode odn odo odp oec oed oee oen oeo oep on- onc ond one onn ono onp oo- ooc ood oon ooo oop op- opc opd ope opn opo opp p-p pcc pcd pce pcn pco pcp pdc pdd pde pdn pdo pdp pec ped pee pen peo pep pn- pnc pnd pne pnn pno pnp poc pod poe pon poo pop ppc ppd ppe ppn ppo ppp