a-a a-c aaa aac aaf aah aak ac- aca acc acf ach ack af- afa afc aff afh afk aha ahc ahf ahh ahk aka akc akh akk c-- caa cac caf cah cak cca ccc ccf cch cck cfa cfc cff cfh cfk ch- cha chc chf chh chk cka ckc ckh faa fac faf fah fak fca fcc fcf fck ffa ffc fff ffh ffk fha fhc fhf fhh fka fkc fkf fkk haa hac haf hah hak hca hcc hcf hch hck hfa hfc hff hfh hfk hha hhc hhf hhh hhk hka hkf hkh hkk ka- kaa kac kaf kah kak kca kcc kch kck kfa kfc kff kfh kha khf khh khk kkc kkh kkk