-er -up c-- ccc cce cco ccp ccr ccu ce- cec cee ceo cep cer ceu co- coc coe coo cop cor cou cpc cpe cpo cpp cpr cpu crc cre cro crp crr cru cuc cue cuo cup cur cuu ec- ecc ece eco ecr ecu eec eee eeo eep eer eo- eoc eoe eoo eop eor eou ep- epc epe epo epp epr epu erc ere ero erp err eru eu- euc eue eup eur oc- occ oco ocp ocr ocu oec oee oeo oep oer oo- ooc ooo oop oor op- opc ope opo opp opr or- orc ore oro orp orr oru ou- ouc oue ouo oup our p-p pcc pce pco pcp pcr pcu pec pee peo pep per peu poc poe poo pop por pou ppc ppe ppo ppp ppr ppu prc pre pro prp prr pru puc pue pup pur puu rcc rce rco rcp rcr rcu re- rec ree reo rep rer reu roc roe roo rop ror rou rpc rpe rpo rpp rpr rpu rrc rrp rrr rru ruc rue ruo rup rur ruu ucc uce uco ucp ucr ucu uec uee uep uer uoc uoe uoo uop uor up- upc upe upo upp upr upu ur- urc ure uro urp urr uru uuc uue uur uuu