-ol c-- ccc cce ccf ccl cco ccs ce- cec cee cef cel ceo ces cfc cfe cff cfl cfo cfs cl- clc cle clf cll clo cls co- coc coe cof col coo cos csc cse csf csl cso css ec- ecc ece ecf ecl eco ecs eec eee eef eel eeo ees ef- efc efe eff efl efo efs elc ele elf ell elo els eo- eoc eoe eof eol eoo eos es- esc ese esf esl eso ess fcc fce fcf fcl fco fcs fec fee fef fel feo fes ffc ffe fff ffl ffo ffs flc fle flf fll flo fls foc foe fof fol foo fos fsc fse fsf fsl fso fss lcc lce lcf lcl lco lcs lec lee lef lel leo les lfc lfe lff lfl lfo lfs llc lle llf lll llo lls loc loe lof lol loo los lsc lse lsf lsl lso lss oc- occ ocf ocl oco ocs oec oee oef oel oeo oes of- ofc ofe off ofl ofo ofs olc ole olf oll olo ols oo- ooc oof ool ooo oos os- osc ose osf osl oso oss scc sce scf scl sco scs se- sec see sef sel seo ses sfc sfe sff sfl sfo sfs slc sle slf sll slo sls soc soe sof sol soo sos ss- ssc sse ssf ssl sso sss