a-a a-b a-z aaa aab aae aah aaz ab- aba abb abe abh abz aea aeb aee aeh aez aha ahb ahe ahh ahz az- aza azb aze azz baa bab bae bah baz bba bbb bbe bbh be- bea beb bee beh bez bha bhb bhe bhh bza bze bzh bzz eaa eab eae eah eaz eba ebb ebe ebh eea eeb eee eha ehb ehe ehh eze ezh ezz haa hab hae hah haz hba hbb hbe hbh hbz he- hea heb hee heh hez hha hhb hhe hhh hhz hze zaa zab zah zaz zbb zea zeb zee zeh zez zha zhe zzz