c-- ccc ccd cce cck ccl ccs cdc cdd cde cdk cdl cds ce- cec ced cee cek cel ces ckc ckd cks cl- clc cld cle clk cll cls csc csd cse csk csl css dcc dcd dce dck dcl dcs ddc ddd dde ddk ddl dds de- dec ded dee dek del des dkc dke dkk dkl dks dl- dlc dld dle dlk dll dls dsc dsd dse dsk dsl dss ec- ecc ecd ece eck ecl ecs ed- edc edd ede edk edl eds eec eed eee eek eel ees ekc ekd eke ekl eks elc eld ele elk ell els es- esc esd ese esk esl ess kcc kcd kce kck kcl kcs kdc kde kdk kdl kds ke- kec ked kee kek kel kes kkc kke kkk kkl kks kl- klc kld kls ksc ksd kse ksk ksl kss lcc lcd lce lck lcl lcs ldc ldd lde ldk ldl lds lec led lee lek lel les lkl lks llc lld lle llk lll lls lsc lsd lse lsk lsl lss scc scd sce sck scl scs sdc sdd sde sdk sdl sds se- sec sed see sek sel ses sk- skc skd ske skk skl sks slc sld sle slk sll sls ss- ssc ssd sse ssk ssl sss