c-- ccc cce cck ccl ccm ce- cec cee cek cel cem ckc ckm cl- clc cle clk cll clm cmc cme cmk cml cmm ec- ecc ece eck ecl ecm eec eee eek eel eem ekc eke ekl elc ele elk ell elm em- emc eme emk eml emm kcc kce kck kcl kcm ke- kec kee kek kel kem kkc kke kkk kkl kkm kl- klc klm kmc kme kmk kml kmm lcc lce lck lcl lcm lec lee lek lel lem lkl llc lle llk lll llm lmc lme lmk lml lmm mc- mcc mce mck mcl mcm mec mee mek mel mem mkc mke mkk mkl mkm mlc mle mlk mll mlm mmc mme mmk mml mmm