a-a a-b a-c a-z aaa aab aac aah aar aaz ab- aba abb abc abh abr abz ac- aca acb acc ach acr acz aha ahb ahc ahh ahr ahz ar- ara arb arc arh arr arz az- aza azb azz baa bab bac bah bar baz bba bbb bbc bbh bbr bca bcb bcc bch bcr bcz bha bhb bhc bhh bhr bra brb brh brr brz bza bzh bzr bzz c-- caa cab cac cah car caz cba cbb cbc cbh cbr cbz cca ccb ccc cch ccr ccz ch- cha chb chc chh chr chz cra crb crc crh crr crz cz- czc haa hab hac hah har haz hba hbb hbc hbh hbr hbz hca hcb hcc hch hcr hha hhb hhc hhh hhr hhz hr- hra hrb hrc hrh hrr hrz ra- raa rab rac rah rar raz rba rbb rbc rbh rbr rca rcb rcc rch rcr rh- rha rhb rhc rhh rhr rra rrb rrc rrh rrr rza rzb zaa zab zac zah zar zaz zbb zbc zbr zha zhc zhr zrh zzr zzz