c-- ccc ccd cce cco ccs ccx cdc cdd cde cdo cds cdx ce- cec ced cee ceo ces cex co- coc cod coe coo cos cox csc csd cse cso css csx cxc cxo cxs cxx dcc dcd dce dco dcs dcx ddc ddd dde ddo dds ddx de- dec ded dee deo des dex doc dod doe doo dos dox dsc dsd dse dso dss dsx dxc dxd dxo dxs dxx ec- ecc ecd ece eco ecs ecx ed- edc edd ede edo eds edx eec eed eee eeo ees eex eo- eoc eod eoe eoo eos es- esc esd ese eso ess esx ex- exc exd exe exo exs exx oc- occ ocd oco ocs ocx odc odd ode odo ods oec oed oee oeo oes oex oo- ooc ood ooo oos oox os- osc osd ose oso oss osx ox- oxc oxo oxx scc scd sce sco scs scx sdc sdd sde sdo sds se- sec sed see seo ses sex soc sod soe soo sos sox ss- ssc ssd sse sso sss ssx sxc sxs xcd xcx xdc xde xds xed xee xes xex xoc xod xoo xos xox xsc xss xxo xxx