c-- ccc ccd cce ccf ccs cct cdc cdd cde cdf cds cdt ce- cec ced cee cef ces cet cfc cfd cfe cff cfs cft csc csd cse csf css cst ctc ctd cte ctf cts ctt dcc dcd dce dcf dcs dct ddc ddd dde ddf dds ddt de- dec ded dee def des det dfc dfd dfe dff dfs dft dsc dsd dse dsf dss dst dtc dtd dte dtf dts dtt ec- ecc ecd ece ecf ecs ect ed- edc edd ede edf eds edt eec eed eee eef ees eet ef- efc efd efe eff efs eft es- esc esd ese esf ess est etc etd ete etf ets ett fcc fcd fce fcf fcs fct fdc fdd fde fdf fds fdt fec fed fee fef fes fet ffc ffd ffe fff ffs fft fsc fsd fse fsf fss fst ftc ftd fte ftf fts ftt scc scd sce scf scs sct sdc sdd sde sdf sds sdt se- sec sed see sef ses set sfc sfd sfe sff sfs sft ss- ssc ssd sse ssf sss sst stc std ste stf sts stt tcc tcd tce tcf tcs tct tdc tdd tde tdf tds tdt te- tec ted tee tef tes tet tfc tfd tfe tff tfs tft tsc tsd tse tsf tss tst ttc ttd tte ttf tts ttt