a-a a-b aaa aab aae aah aam aao ab- aba abb abe abh abm abo aea aeb aee aeh aem aeo aha ahb ahe ahh ahm aho ama amb ame amh amm amo aoa aob aoe aoh aom aoo baa bab bae bah bam bao bba bbb bbe bbh bbm bbo be- bea beb bee beh bem beo bha bhb bhe bhh bhm bho bma bmb bme bmh bmm bmo boa bob boe boh bom boo eaa eab eae eah eam eao eba ebb ebe ebh ebm ebo eea eeb eee eem eeo eha ehb ehe ehh ehm eho em- ema emb eme emh emm emo eo- eoa eob eoe eoh eom eoo haa hab hae hah ham hao hba hbb hbe hbh hbm hbo he- hea heb hee heh hem heo hha hhb hhe hhh hhm hho hma hmb hme hmh hmm hmo hoa hob hoe hoh hom hoo m-o maa mab mae mah mam mao mba mbb mbe mbh mbm mbo mea meb mee meh mem meo mha mhh mhm mho mma mmb mme mmh mmm mmo moa mob moe moh mom moo oaa oab oae oah oam oao ob- oba obb obe obh obm obo oea oeb oee oeh oem oeo oha ohe ohh ohm oho om- oma omb ome omh omm omo oo- ooa oob ooh oom ooo