a-do aaaa aaab aaac aaad aaba aabb aabc aabd aaca aacb aacc aacd aaco aada aadc aaoo abaa abab abac abad abb- abba abbb abbo abca abcb abcc abcd abda abdo aboa abob abod aboo abza acaa acab acac acad acba acca accc accd acco acda acdb acdc acoa acod adaa adab adac adad adao adba adbc adcc adda addc addd addo adob adoc adod adoo aoba aoca aza- azab azad azaz azca azo- azoo azza azzo baaa baad baaz baba babb babo bac- baca bacc baco bacz bada badb badd bado baza bazo bbad bbbb bbdd bbdo bcaa bcbc bcca bccc bcda bcoz bdbc bddc boab boac boad boaz boba bobb bobo boca boco boda bodb bodo boob booc bood booz boza bozo bzzz c-bo c-cd caaa caab caac caba cabo cac- caca cacc caco cada cadc cadd cado caod caoz caza cazo cbac cbbc cbca cbcc cbdb cbdc cbdo ccaa ccab ccac ccad ccba ccbc ccca cccb cccc ccdc ccob ccoc ccod cdaa cdac cdad cdba cdda cddb cdza coad coba cobb cobo coca coco coda codd coob cood cozd cozz d-bo daab daad daba dabb dabo daca dada dado dazz dbcc dcbc dcca dccb dccc dcdb dddd ddoc doab doba dobb doca doco dod- doda dodd dodo doob dood doza dozo dzbb dzca obad obba obbo ocab ocac ocad ocbc occa occc odac odbo odda oddd odoo ooaa ooba ooda oooo ozd zaba zabo zaca zada zaza zobo zoco zoda zodd zoo- zoza zozo zzzz