c-- ccc ccd cce ccf ccl ccs cct cdc cdd cde cdf cdl cds cdt ce- cec ced cee cef cel ces cet cfc cfd cfe cff cfl cfs cft cl- clc cld cle clf cll cls clt csc csd cse csf csl css cst ctc ctd cte ctf ctl cts ctt dcc dcd dce dcf dcl dcs dct ddc ddd dde ddf ddl dds ddt de- dec ded dee def del des det dfc dfd dfe dff dfl dfs dft dl- dlc dld dle dlf dll dls dlt dsc dsd dse dsf dsl dss dst dtc dtd dte dtf dtl dts dtt ec- ecc ecd ece ecf ecl ecs ect ed- edc edd ede edf edl eds edt eec eed eee eef eel ees eet ef- efc efd efe eff efl efs eft elc eld ele elf ell els elt es- esc esd ese esf esl ess est etc etd ete etf etl ets ett fcc fcd fce fcf fcl fcs fct fdc fdd fde fdf fdl fds fdt fec fed fee fef fel fes fet ffc ffd ffe fff ffl ffs fft flc fld fle flf fll fls flt fsc fsd fse fsf fsl fss fst ftc ftd fte ftf ftl fts ftt lcc lcd lce lcf lcl lcs lct ldc ldd lde ldf ldl lds ldt lec led lee lef lel les let lfc lfd lfe lff lfl lfs lft llc lld lle llf lll lls llt lsc lsd lse lsf lsl lss lst ltc ltd lte ltf ltl lts ltt scc scd sce scf scl scs sct sdc sdd sde sdf sdl sds sdt se- sec sed see sef sel ses set sfc sfd sfe sff sfl sfs sft slc sld sle slf sll sls slt ss- ssc ssd sse ssf ssl sss sst stc std ste stf stl sts stt tcc tcd tce tcf tcl tcs tct tdc tdd tde tdf tdl tds tdt te- tec ted tee tef tel tes tet tfc tfd tfe tff tfl tfs tft tlc tld tle tlf tll tls tlt tsc tsd tse tsf tsl tss tst ttc ttd tte ttf ttl tts ttt