c-- ccc ccd cce ccf ccl cdc cdd cde cdf cdl ce- cec ced cee cef cel cfc cfd cfe cff cfl cl- clc cld cle clf cll dcc dcd dce dcf dcl ddc ddd dde ddf ddl de- dec ded dee def del dfc dfd dfe dff dfl dl- dlc dld dle dlf dll ec- ecc ecd ece ecf ecl ed- edc edd ede edf edl eec eed eee eef eel ef- efc efd efe eff efl elc eld ele elf ell fcc fcd fce fcf fcl fdc fdd fde fdf fdl fec fed fee fef fel ffc ffd ffe fff ffl flc fld fle flf fll lcc lcd lce lcf lcl ldc ldd lde ldf ldl lec led lee lef lel lfc lfd lfe lff lfl llc lld lle llf lll