c-- ccc ccd cce cco ccs cct cdc cdd cde cdo cds cdt ce- cec ced cee ceo ces cet co- coc cod coe coo cos cot csc csd cse cso css cst ctc ctd cte cto cts ctt dcc dcd dce dco dcs dct ddc ddd dde ddo dds ddt de- dec ded dee deo des det doc dod doe doo dos dot dsc dsd dse dso dss dst dtc dtd dte dto dts dtt ec- ecc ecd ece eco ecs ect ed- edc edd ede edo eds edt eec eed eee eeo ees eet eo- eoc eod eoe eoo eos eot es- esc esd ese eso ess est etc etd ete eto ets ett oc- occ ocd oco ocs oct odc odd ode odo ods odt oec oed oee oeo oes oet oo- ooc ood ooo oos oot os- osc osd ose oso oss ost ot- otc otd ote oto ots ott scc scd sce sco scs sct sdc sdd sde sdo sds sdt se- sec sed see seo ses set soc sod soe soo sos sot ss- ssc ssd sse sso sss sst stc std ste sto sts stt tcc tcd tce tco tcs tct tdc tdd tde tdo tds tdt te- tec ted tee teo tes tet to- toc tod toe too tos tot tsc tsd tse tso tss tst ttc ttd tte tto tts ttt