a-do aaaa aaab aaac aaad aaal aaba aabb aabc aabd aabl aaca aacb aacc aacd aacl aaco aada aadc aala aalc aald aall aalo aaoo abaa abab abac abad abal abb- abba abbb abbo abca abcb abcc abcd abcl abda abdo abla ablo aboa abob abod abol aboo acaa acab acac acad acba acbl acca accc accd acco acda acdb acdc acla aclc acoa acod acol adaa adab adac adad adal adao adba adbc adcc adda addc addd addl addo adob adoc adod adoo alaa alac alad alal alao alb- alba albc albo alca alcc alco ald- alda aldl aldo all- alla alll allo aloa aloc alod alol aloo aoba aoca aola baaa baad baal baba babb babo bac- baca bacc baco bada badb badd bado bala balc bald ball balo baol bbad bbbb bbdd bbdo bblb bcaa bcbc bcca bccc bccl bcda bdbc bddc blaa blab blac blad bldc blob bloc blod bloo boab boac boad boal boba bobb bobo boca boco boda bodb bodo bola bold boll bolo boob booc bood bool c-bo c-cd caaa caab caac caal caba cabo cac- caca cacc caco cada cadc cadd cado cala calc cald call calo caod caol cbac cbal cbbc cbca cbcc cbcl cbdb cbdc cbdo cblb cblc cbol ccaa ccab ccac ccad ccba ccbc ccca cccb cccc cccl ccdc ccla cclc ccob ccoc ccod cdaa cdac cdad cdba cdda cddb cddl clab clad clcd cldc clob clod cloo coad coal coba cobb cobo coca coco coda codd codl col- cola colb cold coll colo coob cood cool d-bo daab daad daal daba dabb dabo daca dada dado dala dall dalo dbcc dcbc dcca dccb dccc dccl dcdb dddd ddlc ddoc dlab dlbd dlco doab doal doba dobb dobl doca doco dod- doda dodd dodo dola dold doll dolo doob dood dool laaa laac laad laal laba labo laca lacc lacl laco lada ladd lado lala lald lall lalo lbcc lcac lcad lcbc lcca lccc lcdd llao llcc lldb lldc lllc llll lloa lloc llod lloo loac load lob- loba lobb lobo loca locc loco loda lola lold loll lolo loob looc lood lool oall obad obal obba obbo obla obol ocab ocac ocad ocal ocbc occa occc oclc odac odal odbo odda oddd odla odoo olac olba olbo olca olcc oldb olla ollo ooaa ooba ooda oola oold oolo oooo