a-a a-b a-c a-z aaa aab aac aaz ab- aba abb abc abz ac- aca acb acc acz az- aza azb azz baa bab bac baz bba bbb bbc bca bcb bcc bcz bza bzz c-- caa cab cac caz cba cbb cbc cbz cca ccb ccc ccz cz- czc zaa zab zac zaz zbb zbc zzz

aaaa aaab aaac aaba aabb aabc aaca aacb aacc abaa abab abac abb- abba abbb abca abcb abcc abza acaa acab acac acba acca accc aza- azab azaz azca azza baaa baaz baba babb bac- baca bacc baza bbbb bcaa bcbc bcca bccc bzzz caaa caab caac caba cac- caca cacc caza cbac cbbc cbca cbcc ccaa ccab ccac ccba ccbc ccca cccb cccc zaba zaca zaza zzzz

-aaa- aabaa aabba aacbc abaab ababa abaca abaza abbac abccc abzac acaca acacb azaca bacab bacca bacza bazac c-a-c ca-ca caaba cazaa cazac ccccc za-za zzzzz

aaaaba abacab azzaba baabaa bacaba bbbbbb zababa zazaca

bac-cab bbbbbbb

bbbbbbbb

abba-zaba baabaabaa

aaaaaaaaaaaaaaa bbbbbbbbbbbbbbb bzzzzzzzzzzzzzz ccccccccccccccc