a-do aaaa aaab aaac aaad aaap aaar aaba aabb aabc aabd aabp aaca aacb aacc aacd aaco aacp aacr aada aadc aaoo aapa aapc aapo aara aarc aard aaro aarp abaa abab abac abad abap abar abb- abba abbb abbo abbr abca abcb abcc abcd abcp abcr abda abdo aboa abob abod aboo abor abpa abpc abpd abpp abpr abra abrc abro acaa acab acac acad acap acar acba acca accc accd acco accp acda acdb acdc acdp acoa acod acop acor acpa acpd acpr acr- acra acrc acro acrr adaa adab adac adad adao adap adar adba adbc adcc adda addc addd addo addr adob adoc adod adoo ador adp- adra adro aoba aoca aopo aora aorb apac apao apap apar apba apbr apca apcb apcc apcd apco apcr apda apdd apo- apoc apod apoo apop apor appa appc appd appr apra aprc apro arab arac arad arap arar arba arc- arca arco arda ardc ardo aroa arob arod aroo aror arpa arr- arra arrc arro arrr baaa baad baar baba babb babo babr bac- baca bacc baco bada badb badd bado badr bapa bapc bapp bar- bara barb barc bard baro barr bbad bbbb bbdd bbdo bbpr bbrc bcaa bcap bcar bcbc bcbp bcca bccc bcda bcor bcpp bcra bd-r bdbc bddc bdpc boab boac boad boar boba bobb bobo boca boco boda bodb bodo boob booc bood boop boor bopa bopp bor- bora bord boro borr bpcp bpda bprc bprd brab brac brad brao brca brcb brda brdo broa brob broc brod broo bror brrr c-bo c-cd caaa caab caac caap caba cabo cac- caca cacc caco cacr cada cadc cadd cado cadr caod caor capa capb capc capd capo capp cara carb carc card caro carp carr cbac cbar cbbc cbca cbcc cbcp cbcr cbdb cbdc cbdo cbpc cbpp cbrd ccaa ccab ccac ccad ccap ccar ccba ccbc ccca cccb cccc cccp ccdc ccdp ccdr ccob ccoc ccod ccpa ccpp ccpr ccra ccrc ccrp cd-r cdaa cdac cdad cdba cdda cddb cddr coad coba cobb cobo coca coco cocp coda codd coob cood coop copa copd copo copp copr cor- cora corb corc cord coro corp corr cpaa cpac cpad cpap cpbc cpca cppa cppd crab crac crap crar crbc crca crcc crcr crda crdc crob croc crod croo crop cror crpc d-bo daab daad daap daar daba dabb dabo dabp daca dada dado dapa dapp dara darb darc dard daro darp darr dbar dbcc dbcp dbpc dbpd dcbc dcca dccb dccc dccp dcdb dcop dcpo dcra dddd ddoc ddpo ddrc doab doap doar doba dobb doca doco dod- doda dodd dodo doob dood doop door dopa dopo dopp dopr dora dorc dord doro dorp dorr dpaa dpac dpbc dpcp dppa dppc draa drab drac drad drap drar drba drbc drca drda drob drod drop drra oara obad obba obbo obor obra obro ocab ocac ocad ocap ocbc occa occc ocpa ocpd ocpp ocra ocro ocrr odac odbo odda oddd odoo odop odor odra odrp ooaa ooba oocr ooda oooo oora oord opap opar opca opo- opor oppa oppo opra orab orac orad orao orar orba orbb orbo orca orco orda ordo oro- oror orpc orra orro paap paar paba paca pacd paco pada padd pado paoc papa papb papp papr par- para parc pard paro parp parr pbac pbar pbcc pboc pbpa pcaa pcad pcap pcba pcbc pcca pccc pcoa pcod pcpb pcpp pcra pcrc pcrd pdac pdca pdcp pdoc pdpa pdpr pdrc poad poar poba pobo poca pocd poco pod- poda podd podo pood poop poor pop- popa popc popo popp pora porb porc poro porr ppac ppad ppap ppar ppcc ppcd ppoa ppod pppa pppd pppo pppp pprc prad prao prar prbc prca prcc prcd prcp pro- proa prob proc prod proo prop prpd prrd raab raad raba rabb rabo rac- raca racc raco rada radc radd rado radr raob raoc raop rapa rapc rapd rapp rara rarb raro rbbb rbbr rcac rcbc rcbo rccb rccc rcdc rcpd rcpo rcrd rdac rdap rdbp rdoc rdpc roab road roap roar rob- roba robb robo roca rocc roco roda rodd rodo roob rood roop roor ropa ropo rora rorc roro rpca rpdp rpob rrad rrrr