-er -up c-- ccc ccd cce ccp ccr ccs ccu cdc cdd cde cdp cdr cds cdu ce- cec ced cee cep cer ces ceu cpc cpd cpe cpp cpr cps cpu crc crd cre crp crr crs cru csc csd cse csp csr css csu cuc cud cue cup cur cus cuu dcc dcd dce dcp dcr dcs dcu ddc ddd dde ddp ddr dds ddu de- dec ded dee dep der des deu dpc dpd dpe dpp dpr dps dpu drc drd dre drp drr drs dru dsc dsd dse dsp dsr dss dsu duc dud due dup dur dus ec- ecc ecd ece ecr ecs ecu ed- edc edd ede edp edr eds edu eec eed eee eep eer ees ep- epc epd epe epp epr eps epu erc erd ere erp err ers eru es- esc esd ese esp esr ess esu eu- euc eud eue eup eur eus p-p pcc pcd pce pcp pcr pcs pcu pdc pdd pde pdp pdr pds pdu pec ped pee pep per pes peu ppc ppd ppe ppp ppr pps ppu prc prd pre prp prr prs pru ps- psc psd pse psp psr pss psu puc pud pue pup pur pus puu rcc rcd rce rcp rcr rcs rcu rdc rdd rde rdp rdr rds rdu re- rec red ree rep rer res reu rpc rpd rpe rpp rpr rps rpu rrc rrd rrp rrr rrs rru rsc rsd rse rsp rsr rss rsu ruc rud rue rup rur rus ruu scc scd sce scp scr scs scu sdc sdd sde sdp sdr sds sdu se- sec sed see sep ser ses seu spc spd spe spp spr sps spu sr- src srd sre srp srr srs ss- ssc ssd sse ssp ssr sss ssu suc sud sue sup sur sus suu ucc ucd uce ucp ucr ucs ucu udc udd ude udp udr uds udu uec ued uee uep uer ues up- upc upd upe upp upr ups upu ur- urc urd ure urp urr urs uru usc usd use usp usr uss usu uuc uue uur uus uuu