bbb bbc bbe bbf bbm bcb bcc bce bcf bcm be- beb bec bee bef bem bfb bfc bfe bff bfm bmb bmc bme bmf bmm c-- cbb cbc cbe cbf cbm ccb ccc cce ccf ccm ce- ceb cec cee cef cem cfb cfc cfe cff cfm cmb cmc cme cmf cmm ebb ebc ebe ebf ebm ec- ecb ecc ece ecf ecm eeb eec eee eef eem ef- efb efc efe eff efm em- emb emc eme emf emm fbb fbc fbe fbf fbm fcb fcc fce fcf fcm feb fec fee fef fem ffc ffe fff ffm fmb fmc fme fmf fmm m-f mbb mbc mbe mbf mbm mc- mcb mcc mce mcf mcm meb mec mee mef mem mfb mfc mfe mff mfm mmb mmc mme mmf mmm