a-a a-b a-i a-t aaa aab aae aai aao aas aat ab- aba abb abe abi abo abs abt aea aeb aee aei aeo aes aet ai- aia aib aie aii aio ais ait aoa aob aoe aoi aoo aos aot as- asa asb ase asi aso ass ast at- ata atb ate ati ato ats att baa bab bae bai bao bas bat bba bbb bbe bbi bbo bbs bbt be- bea beb bee bei beo bes bet bi- bia bib bie bii bio bis bit boa bob boe boi boo bos bot bsa bsb bse bsi bso bss bst bta btb bte bti bto bts btt eaa eab eae eai eao eas eat eba ebb ebe ebi ebo ebs ebt eea eeb eee eeo ees eet eia eib eie eii eio eis eit eo- eoa eob eoe eoi eoo eos eot es- esa esb ese esi eso ess est eta etb ete eti eto ets ett ia- iaa iab iae iai iao ias iat iba ibb ibe ibi ibo ibs ibt ie- iea iee iei ies iet iia iib iie iii iio iis iit io- ioa iob ioe ioi ioo ios iot is- isa isb ise isi iso iss ist ita itb ite iti ito its itt o-i oaa oab oae oai oao oas oat ob- oba obb obe obi obo obs obt oea oeb oee oei oeo oes oet oia oib oie oii oio ois oit oo- ooa oob ooi ooo oos oot os- osa osb ose osi oso oss ost ot- ota otb ote oti oto ots ott saa sab sae sai sao sas sat sba sbb sbe sbi sbo sbs sbt se- sea seb see sei seo ses set sia sib sie sii sio sis sit soa sob soe soi soo sos sot ss- ssa ssb sse ssi sso sss sst sta stb ste sti sto sts stt taa tab tae tai tao tas tat tba tbb tbe tbi tbo tbs tbt te- tea teb tee tei teo tes tet tia tib tie tii tio tis tit to- toa tob toe toi too tos tot tsa tsb tse tsi tso tss tst tta ttb tte tti tto tts ttt