a-a a-c aaa aac aae aaf aah ac- aca acc ace acf ach aea aec aee aef aeh af- afa afc afe aff afh aha ahc ahe ahf ahh c-- caa cac cae caf cah cca ccc cce ccf cch ce- cea cec cee cef ceh cfa cfc cfe cff cfh ch- cha chc che chf chh eaa eac eae eaf eah ec- eca ecc ece ecf ech eea eec eee eef ef- efa efc efe eff efh eha ehc ehe ehf ehh faa fac fae faf fah fca fcc fce fcf fea fec fee fef feh ffa ffc ffe fff ffh fha fhc fhe fhf fhh haa hac hae haf hah hca hcc hce hcf hch he- hea hec hee hef heh hfa hfc hfe hff hfh hha hhc hhe hhf hhh