-er c-- ccc ccd cce ccp ccr ccx cdc cdd cde cdp cdr cdx ce- cec ced cee cep cer cex cpc cpd cpe cpp cpr cpx crc crd cre crp crr crx cxc cxp cxr cxx dcc dcd dce dcp dcr dcx ddc ddd dde ddp ddr ddx de- dec ded dee dep der dex dpc dpd dpe dpp dpr drc drd dre drp drr drx dxc dxd dxp dxr dxx ec- ecc ecd ece ecr ecx ed- edc edd ede edp edr edx eec eed eee eep eer eex ep- epc epd epe epp epr epx erc erd ere erp err ex- exc exd exe exp exr exx p-p pcc pcd pce pcp pcr pcx pdc pdd pde pdp pdr pdx pec ped pee pep per pex ppc ppd ppe ppp ppr ppx prc prd pre prp prr prx pxc pxe pxr rcc rcd rce rcp rcr rcx rdc rdd rde rdp rdr rdx re- rec red ree rep rer rex rpc rpd rpe rpp rpr rpx rrc rrd rrp rrr rxp rxr xcd xcp xcr xcx xdc xde xdr xed xee xep xer xex xpc xpd xpe xpp xrc xrd xrx xxp xxx