c-- ccc cce ccf ccl ccs cct ce- cec cee cef cel ces cet cfc cfe cff cfl cfs cft cl- clc cle clf cll cls clt csc cse csf csl css cst ctc cte ctf ctl cts ctt ec- ecc ece ecf ecl ecs ect eec eee eef eel ees eet ef- efc efe eff efl efs eft elc ele elf ell els elt es- esc ese esf esl ess est etc ete etf etl ets ett fcc fce fcf fcl fcs fct fec fee fef fel fes fet ffc ffe fff ffl ffs fft flc fle flf fll fls flt fsc fse fsf fsl fss fst ftc fte ftf ftl fts ftt lcc lce lcf lcl lcs lct lec lee lef lel les let lfc lfe lff lfl lfs lft llc lle llf lll lls llt lsc lse lsf lsl lss lst ltc lte ltf ltl lts ltt scc sce scf scl scs sct se- sec see sef sel ses set sfc sfe sff sfl sfs sft slc sle slf sll sls slt ss- ssc sse ssf ssl sss sst stc ste stf stl sts stt tcc tce tcf tcl tcs tct te- tec tee tef tel tes tet tfc tfe tff tfl tfs tft tlc tle tlf tll tls tlt tsc tse tsf tsl tss tst ttc tte ttf ttl tts ttt