-er c-- ccc ccd cce ccr ccs ccv cdc cdd cde cdr cds cdv ce- cec ced cee cer ces cev crc crd cre crr crs crv csc csd cse csr css csv cvc cvd cve cvr cvs cvv dcc dcd dce dcr dcs dcv ddc ddd dde ddr dds de- dec ded dee der des dev drc drd dre drr drs drv dsc dsd dse dsr dss dsv dvc dvd dve dvr dvs ec- ecc ecd ece ecr ecs ecv ed- edc edd ede edr eds eec eed eee eer ees eev erc erd ere err ers erv es- esc esd ese esr ess esv evc evd eve evr evs evv rcc rcd rce rcr rcs rcv rdc rdd rde rdr rds rdv re- rec red ree rer res rev rrc rrd rrr rrs rsc rsd rse rsr rss rsv rvc rvd rve rvr rvs rvv scc scd sce scr scs scv sdc sdd sde sdr sds sdv se- sec sed see ser ses sev sr- src srd sre srr srs srv ss- ssc ssd sse ssr sss ssv svc svd sve svr svs svv v-e vcc vcd vce vcr vcs vdc vdd vde vdr vds vdv vec ved vee ver ves vrc vrd vre vrr vrs vsc vsd vse vsr vss vsv vvc vvr vvs vvv