a-a a-b a-c a-t aaa aab aac aao aap aar aat ab- aba abb abc abo abp abr abt ac- aca acb acc aco acp acr act aoa aob aoc aoo aop aor aot ap- apa apb apc apo app apr apt ar- ara arb arc aro arp arr art at- ata atb atc ato atp atr att b-p baa bab bac bao bap bar bat bba bbb bbc bbo bbp bbr bbt bca bcb bcc bco bcp bcr bct boa bob boc boo bop bor bot bpa bpb bpc bpo bpp bpr bpt bra brb bro brp brr brt bta btb btc bto btp btr btt c-- caa cab cac cao cap car cat cba cbb cbc cbo cbp cbr cbt cca ccb ccc cco ccp ccr cct co- coa cob coc coo cop cor cot cpa cpb cpc cpo cpp cpr cpt cra crb crc cro crp crr crt cta ctb ctc cto ctp ctr ctt oaa oab oac oao oap oar oat ob- oba obb obc obo obp obr obt oc- oca ocb occ oco ocp ocr oct oo- ooa oob ooc ooo oop oor oot op- opa opb opc opo opp opr opt or- ora orb orc oro orp orr ort ot- ota otb otc oto otp otr ott p-p paa pab pac pao pap par pat pba pbb pbc pbo pbp pbr pbt pca pcb pcc pco pcp pcr pct poa pob poc poo pop por pot ppa ppb ppc ppo ppp ppr ppt pra prb prc pro prp prr prt pt- pta ptb ptc pto ptp ptr ptt ra- raa rab rac rao rap rar rat rba rbb rbc rbo rbp rbr rbt rca rcb rcc rco rcp rcr rct roa rob roc roo rop ror rot rpa rpb rpc rpo rpp rpr rpt rra rrb rrc rrp rrr rrt rta rtb rtc rto rtp rtr rtt taa tab tac tao tap tar tat tba tbb tbc tbo tbp tbr tbt tca tcb tcc tco tcp tcr tct to- toa tob toc too top tor tot tpa tpb tpc tpo tpp tpr tpt tra trb trc tro trp trr trt tta ttb ttc tto ttp ttr ttt

aaaa aaab aaac aaap aaar aaba aabb aabc aabp aabt aaca aacb aacc aaco aacp aacr aact aaoo aapa aapc aapo aapt aara aarc aaro aarp aart aata aatc aatt abaa abab abac abap abar abat abb- abba abbb abbo abbr abbt abca abcb abcc abcp abcr abct aboa abob aboo abor abot abpa abpc abpp abpr abra abrc abro abta ac-t acaa acab acac acap acar acat acba acca accc acco accp acct acoa acop acor acot acpa acpr acpt acr- acra acrc acro acrr acta actc acto actt aoba aoca aopo aora aorb aort aotc apac apao apap apar apat apba apbr apca apcb apcc apco apcr apo- apoc apoo apop apor apot appa appc appr appt apra aprc apro aprt apta aptc aptt arab arac arap arar arat arba arc- arca arco arct aroa arob aroo aror arpa arr- arra arrc arro arrr arrt arta artc arto artr at-t ataa atab atac atap atar atat atca atcc atco atcr atob atoc atop ator atot atpr atra atrc atro atrp atta atto attp attr baaa baar baat baba babb babo babr bac- baca bacc baco bact bapa bapc bapp bapt bar- bara barb barc baro barr bart bata batc bato batt bbbb bbpr bbrc bcaa bcap bcar bcat bcbc bcbp bcca bccc bcor bcpp bcra bctc boab boac boar boat boba bobb bobo boca boco boob booc boop boor boot bopa bopp bor- bora boro borr bort bota botb boto bott bpcp bpot bprc brab brac brao brat brca brcb broa brob broc broo bror brot brrr brtc btaa btbp btcc btob btor btrc btrt bttb c-bo caaa caab caac caap caat caba cabo cac- caca cacc caco cacr caor capa capb capc capo capp capt cara carb carc caro carp carr cart cat- cata catb catc cato catt cbac cbar cbat cbbc cbca cbcc cbcp cbcr cbct cbot cbpc cbpp cbrt cbta cbtc ccaa ccab ccac ccap ccar ccat ccba ccbc ccca cccb cccc cccp ccob ccoc ccpa ccpp ccpr ccra ccrc ccrp ccrt cctb cctc cctt coat coba cobb cobo coca coco cocp coct coob coop coot copa copo copp copr copt cor- cora corb corc coro corp corr cort cota cotb cotc coto cott cpaa cpac cpap cpbc cpca cppa cprt cptp cptr crab crac crap crar crat crbc crca crcc crcr crob croc croo crop cror crot crpc crrt crtc crtp ctab ctba ctca ctcp ctor ctot ctpo ctpp ctrc ctrp ctta oara obba obbo obor obot obra obro ocab ocac ocap ocat ocbc occa occc occt ocpa ocpp ocra ocro ocrr oct- octa octo ooaa ooba oocr oooo oora oort ootb ootp opap opar opca opo- opor oppa oppo opra opto orab orac orao orar orat orba orbb orbo orca orco oro- oror orot orpc orra orro orta ortc orto otac otap otar oto- otoo otor otpp otra otro otta otto paap paar paat paba pabt paca paco pact paoc papa papb papp papr par- para parc paro parp parr part pata pato patr patt pbac pbar pbcc pboc pbpa pcaa pcap pcba pcbc pcca pccc pcoa pcpb pcpp pcra pcrc poar poat poba pobo poca poco poop poor poot pop- popa popc popo popp popt pora porb porc poro porr port pota potc poto pott ppac ppap ppar ppcc ppoa pppa pppo pppp pprc ppta pptt prao prar prat prbc prca prcc prcp pro- proa prob proc proo prop prot prtc prtp prtr ptab ptca ptcc ptop pttc raab raat raba rabb rabo rac- raca racc raco ract raob raoc raop rapa rapc rapp rapt rara rarb raro rata rato ratp ratt rbbb rbbr rcac rcbc rcbo rccb rccc rcpo rcpt rctc roab roap roar roat rob- roba robb robo robt roca rocc roco roob roop roor root ropa ropo rora rorc roro rort rota rotc roto rotr rott