-al a-a a-b a-c aaa aab aac aad aae aaf aal ab- aba abb abc abd abe abf abl ac- aca acb acc acd ace acf acl ad- ada adb adc add ade adf adl aea aeb aec aed aee aef ael af- afa afb afc afd afe aff afl al- ala alb alc ald ale alf all baa bab bac bad bae baf bal bba bbb bbc bbd bbe bbf bbl bca bcb bcc bcd bce bcf bcl bda bdb bdc bdd bde bdf bdl be- bea beb bec bed bee bef bel bfa bfb bfc bfd bfe bff bfl bla blb blc bld ble blf bll c-- caa cab cac cad cae caf cal cba cbb cbc cbd cbe cbf cbl cca ccb ccc ccd cce ccf ccl cda cdb cdc cdd cde cdf cdl ce- cea ceb cec ced cee cef cel cfa cfb cfc cfd cfe cff cfl cl- cla clb clc cld cle clf cll daa dab dac dad dae daf dal dba dbb dbc dbd dbe dbf dbl dca dcb dcc dcd dce dcf dcl dda ddb ddc ddd dde ddf ddl de- dea deb dec ded dee def del dfa dfb dfc dfd dfe dff dfl dl- dla dlb dlc dld dle dlf dll eaa eab eac ead eae eaf eal eba ebb ebc ebd ebe ebf ebl ec- eca ecb ecc ecd ece ecf ecl ed- eda edb edc edd ede edf edl eea eeb eec eed eee eef eel ef- efa efb efc efd efe eff efl ela elb elc eld ele elf ell faa fab fac fad fae faf fal fba fbb fbc fbd fbe fbf fbl fca fcb fcc fcd fce fcf fcl fda fdb fdc fdd fde fdf fdl fea feb fec fed fee fef fel ffa ffc ffd ffe fff ffl fla flb flc fld fle flf fll la- laa lab lac lad lae laf lal lba lbb lbc lbd lbe lbf lbl lca lcb lcc lcd lce lcf lcl lda ldb ldc ldd lde ldf ldl lea leb lec led lee lef lel lfa lfb lfc lfd lfe lff lfl lla llb llc lld lle llf lll