aaaa aaab aaac aaal aaba aabb aabc aabl aaca aacb aacc aacl aaco aala aalc aall aalo aaoo abaa abab abac abal abb- abba abbb abbo abca abcb abcc abcl abla ablo aboa abob abol aboo acaa acab acac acba acbl acca accc acco acla aclc acoa acol alaa alac alal alao alb- alba albc albo alca alcc alco all- alla alll allo aloa aloc alol aloo aoba aoca aola baaa baal baba babb babo bac- baca bacc baco bala balc ball balo baol bbbb bblb bcaa bcbc bcca bccc bccl blaa blab blac blob bloc bloo boab boac boal boba bobb bobo boca boco bola boll bolo boob booc bool c-bo caaa caab caac caal caba cabo cac- caca cacc caco cala calc call calo caol cbac cbal cbbc cbca cbcc cbcl cblb cblc cbol ccaa ccab ccac ccba ccbc ccca cccb cccc cccl ccla cclc ccob ccoc clab clob cloo coal coba cobb cobo coca coco col- cola colb coll colo coob cool laaa laac laal laba labo laca lacc lacl laco lala lall lalo lbcc lcac lcbc lcca lccc llao llcc lllc llll lloa lloc lloo loac lob- loba lobb lobo loca locc loco lola loll lolo loob looc lool oall obal obba obbo obla obol ocab ocac ocal ocbc occa occc oclc olac olba olbo olca olcc olla ollo ooaa ooba oola oolo oooo