-er c-- ccc ccd cce ccr ccs cct ccu ccx cdc cdd cde cdr cds cdt cdu cdx ce- cec ced cee cer ces cet ceu cex crc crd cre crr crs crt cru crx csc csd cse csr css cst csu csx ctc ctd cte ctr cts ctt ctu ctx cuc cud cue cur cus cut cuu cxc cxr cxs cxt cxx dcc dcd dce dcr dcs dct dcu dcx ddc ddd dde ddr dds ddt ddu ddx de- dec ded dee der des det deu dex drc drd dre drr drs drt dru drx dsc dsd dse dsr dss dst dsu dsx dtc dtd dte dtr dts dtt dtu dtx duc dud due dur dus dut dux dxc dxd dxr dxs dxt dxx ec- ecc ecd ece ecr ecs ect ecu ecx ed- edc edd ede edr eds edt edu edx eec eed eee eer ees eet eex erc erd ere err ers ert eru es- esc esd ese esr ess est esu esx etc etd ete etr ets ett etu etx eu- euc eud eue eur eus eut eux ex- exc exd exe exr exs ext exu exx rcc rcd rce rcr rcs rct rcu rcx rdc rdd rde rdr rds rdt rdu rdx re- rec red ree rer res ret reu rex rrc rrd rrr rrs rrt rru rsc rsd rse rsr rss rst rsu rsx rtc rtd rte rtr rts rtt rtu rtx ruc rud rue rur rus rut ruu rux rxr rxs scc scd sce scr scs sct scu scx sdc sdd sde sdr sds sdt sdu se- sec sed see ser ses set seu sex sr- src srd sre srr srs srt srx ss- ssc ssd sse ssr sss sst ssu ssx stc std ste str sts stt stu stx suc sud sue sur sus sut suu sux sxc sxs sxt sxu t-x tcc tcd tce tcr tcs tct tcu tcx tdc tdd tde tdr tds tdt tdu tdx te- tec ted tee ter tes tet teu tex trc trd tre trr trs trt tru trx tsc tsd tse tsr tss tst tsu tsx ttc ttd tte ttr tts ttt ttu ttx tuc tud tue tur tus tut tuu tux txe txs txt txu ucc ucd uce ucr ucs uct ucu udc udd ude udr uds udt udu udx uec ued uee uer ues uet ur- urc urd ure urr urs urt uru urx usc usd use usr uss ust usu usx utc utd ute utr uts utt utu utx uuc uue uur uus uut uuu uxc uxr uxt uxu xcd xcr xcx xdc xde xdr xds xdt xed xee xer xes xet xeu xex xrc xrd xrt xrx xsc xss xst xtc xtr xts xtx xue xus xxx