a-a a-b a-t aaa aab aae aao aap aas aat ab- aba abb abe abo abp abs abt aea aeb aee aeo aep aes aet aoa aob aoe aoo aop aos aot ap- apa apb ape apo app aps apt as- asa asb ase aso asp ass ast at- ata atb ate ato atp ats att b-p baa bab bae bao bap bas bat bba bbb bbe bbo bbp bbs bbt be- bea beb bee beo bep bes bet boa bob boe boo bop bos bot bpa bpb bpe bpo bpp bps bpt bsa bsb bse bso bsp bss bst bta btb bte bto btp bts btt eaa eab eae eao eap eas eat eba ebb ebe ebo ebp ebs ebt eea eeb eee eeo eep ees eet eo- eoa eob eoe eoo eop eos eot ep- epa epb epe epo epp eps ept es- esa esb ese eso esp ess est eta etb ete eto etp ets ett oaa oab oae oao oap oas oat ob- oba obb obe obo obp obs obt oea oeb oee oeo oep oes oet oo- ooa oob ooo oop oos oot op- opa opb ope opo opp ops opt os- osa osb ose oso osp oss ost ot- ota otb ote oto otp ots ott p-p paa pab pae pao pap pas pat pba pbb pbe pbo pbp pbs pbt pea peb pee peo pep pes pet poa pob poe poo pop pos pot ppa ppb ppe ppo ppp pps ppt ps- psa psb pse pso psp pss pst pt- pta ptb pte pto ptp pts ptt saa sab sae sao sap sas sat sba sbb sbe sbo sbp sbs sbt se- sea seb see seo sep ses set soa sob soe soo sop sos sot spa spb spe spo spp sps spt ss- ssa ssb sse sso ssp sss sst sta stb ste sto stp sts stt taa tab tae tao tap tas tat tba tbb tbe tbo tbp tbs tbt te- tea teb tee teo tep tes tet to- toa tob toe too top tos tot tpa tpb tpe tpo tpp tps tpt tsa tsb tse tso tsp tss tst tta ttb tte tto ttp tts ttt