-al a-a a-b a-c aaa aab aac aae aaf aah aal ab- aba abb abc abe abf abh abl ac- aca acb acc ace acf ach acl aea aeb aec aee aef aeh ael af- afa afb afc afe aff afh afl aha ahb ahc ahe ahf ahh ahl al- ala alb alc ale alf alh all baa bab bac bae baf bah bal bba bbb bbc bbe bbf bbh bbl bca bcb bcc bce bcf bch bcl be- bea beb bec bee bef beh bel bfa bfb bfc bfe bff bfh bfl bha bhb bhc bhe bhf bhh bhl bla blb blc ble blf blh bll c-- caa cab cac cae caf cah cal cba cbb cbc cbe cbf cbh cbl cca ccb ccc cce ccf cch ccl ce- cea ceb cec cee cef ceh cel cfa cfb cfc cfe cff cfh cfl ch- cha chb chc che chf chh chl cl- cla clb clc cle clf clh cll eaa eab eac eae eaf eah eal eba ebb ebc ebe ebf ebh ebl ec- eca ecb ecc ece ecf ech ecl eea eeb eec eee eef eel ef- efa efb efc efe eff efh efl eha ehb ehc ehe ehf ehh ehl ela elb elc ele elf elh ell faa fab fac fae faf fah fal fba fbb fbc fbe fbf fbh fbl fca fcb fcc fce fcf fcl fea feb fec fee fef feh fel ffa ffc ffe fff ffh ffl fha fhb fhc fhe fhf fhh fhl fla flb flc fle flf fll haa hab hac hae haf hah hal hba hbb hbc hbe hbf hbh hbl hca hcb hcc hce hcf hch hcl he- hea heb hec hee hef heh hel hfa hfb hfc hfe hff hfh hfl hha hhb hhc hhe hhf hhh hhl hla hlb hlc hle hlf hlh hll la- laa lab lac lae laf lah lal lba lbb lbc lbe lbf lbh lbl lca lcb lcc lce lcf lch lcl lea leb lec lee lef leh lel lfa lfb lfc lfe lff lfh lfl lha lhb lhc lhf lhh lla llb llc lle llf lll