c-- ccc cce ccf ccl ccn ccs ce- cec cee cef cel cen ces cfc cfe cff cfl cfn cfs cl- clc cle clf cll cln cls cn- cnc cne cnf cnl cnn cns csc cse csf csl csn css ec- ecc ece ecf ecl ecn ecs eec eee eef eel een ees ef- efc efe eff efl efs elc ele elf ell eln els en- enc ene enf enl enn ens es- esc ese esf esl esn ess fcc fce fcf fcl fcn fcs fec fee fef fel fen fes ffc ffe fff ffl ffn ffs flc fle flf fll fln fls fnc fne fnf fnl fnn fns fsc fse fsf fsl fsn fss lcc lce lcf lcl lcn lcs lec lee lef lel len les lfc lfe lff lfl lfn lfs llc lle llf lll lln lls lnc lne lnl lnn lns lsc lse lsf lsl lsn lss ncc nce ncf ncl ncn ncs ne- nec nee nef nel nen nes nfc nfe nff nfl nfn nfs nlc nle nlf nll nln nls nnc nne nnf nnl nnn nns nsc nse nsf nsl nsn nss scc sce scf scl scn scs se- sec see sef sel sen ses sfc sfe sff sfl sfn sfs slc sle slf sll sln sls snc sne snf snl snn sns ss- ssc sse ssf ssl ssn sss