-er c-- ccc cce ccf ccp ccr cct ce- cec cee cef cep cer cet cfc cfe cff cfp cfr cft cpc cpe cpf cpp cpr cpt crc cre crf crp crr crt ctc cte ctf ctp ctr ctt ec- ecc ece ecf ecr ect eec eee eef eep eer eet ef- efc efe eff efp efr eft ep- epc epe epf epp epr ept erc ere erf erp err ert etc ete etf etp etr ett fcc fce fcf fcp fcr fct fec fee fef fep fer fet ffc ffe fff ffp ffr fft fpc fpe fpp fpr fpt frc fre frf frp frr frt ftc fte ftf ftp ftr ftt p-p pcc pce pcf pcp pcr pct pec pee pef pep per pet pfc pfe pff pfp pfr pft ppc ppe ppf ppp ppr ppt prc pre prf prp prr prt pt- ptc pte ptf ptp ptr ptt rcc rce rcf rcp rcr rct re- rec ree ref rep rer ret rfc rfe rff rfp rfr rft rpc rpe rpf rpp rpr rpt rrc rrf rrp rrr rrt rtc rte rtf rtp rtr rtt tcc tce tcf tcp tcr tct te- tec tee tef tep ter tet tfc tfe tff tfp tfr tft tpc tpe tpf tpp tpr tpt trc tre trf trp trr trt ttc tte ttf ttp ttr ttt