aaaa aaab aaac aaad aaal aaba aabb aabc aabd aabl aaca aacb aacc aacd aacl aacu aada aadc aadu aala aalc aald aall aalu abaa abab abac abad abal abau abb- abba abbb abca abcb abcc abcd abcl abda abdu abla abua abud abul acaa acab acac acad acba acbl acca accc accd accu acda acdb acdc acla aclc aclu acu- acul adaa adab adac adad adal adba adbc adcc adda addc addd addl addu adua adub alaa alac alad alal alau alb- alba albc albu alca alcc ald- alda aldl all- alla alll allu alua auaa auca audc aul- aula auld aull aulu baaa baad baal baba babb babu bac- baca bacc bada badb badd badu bala balc bald ball balu bau- baud baul bbad bbau bbbb bbdd bblb bcaa bcbc bcca bccc bccl bcda bcuc bdbc bddc blaa blab blac blad blau blcu bldc blub blud buad bual buba bubb bubu buca bucc bucu buda budb budd budl budu bula bulb buld bull bulu c-cd caaa caab caac caal caba cabu cac- caca cacc cada cadc cadd cadu cala calc cald call calu cauc caul cbac cbal cbbc cbca cbcc cbcl cbcu cbdb cbdc cblb cblc ccaa ccab ccac ccad ccba ccbc ccca cccb cccc cccl cccu ccdc ccla cclc ccuc cdaa cdac cdad cdba cdda cddb cddl clab clad clau clcd cldc club clud cuau cub- cuba cubb cuca cucc cuda cula culb culc culd cull daab daad daal daau daba dabb dabu daca dada dadu dala dall dalu daub daud dbcc dcbc dcca dccb dccc dccl dccu dcdb dddd ddlc ddub dlab dlbd duaa duab duad dual dub- duba dubb dubc dubu duca duda dudd dudu dula dulc dull dulu duul laaa laac laad laal laba labu laca lacc lacl lacu lada ladd ladu lala lald lall lalu laub laud laul lbcc lcac lcad lcbc lcca lccc lcdd llcc lldb lldc lllc llll llud luau luba luca luda ludd lula lull lulu luua uabc uaca uald uaua ubac ubal ubba ubla ubud ucad ucal ucbc ucca ucdc ucdd ucla ucua udaa udad udal udau udbc udca ulaa ulad ulbc ulcc ulla ulua ulul uulu uuuu