b-u bbb bbe bbf bbi bbs bbt bbu bbx be- beb bee bef bei bes bet beu bex bfb bfe bff bfi bfs bft bfu bfx bi- bib bie bif bii bis bit biu bix bsb bse bsf bsi bss bst bsu bsx btb bte btf bti bts btt btu btx bub bue buf bui bus but buu bux bxb bxi bxx ebb ebe ebf ebi ebs ebt ebu ebx eeb eee eef ees eet eex ef- efb efe eff efi efs eft efx eib eie eif eii eis eit eiu eix es- esb ese esf esi ess est esu esx etb ete etf eti ets ett etu etx eu- eub eue euf eui eus eut eux ex- exe exi exs ext exu exx fbb fbe fbf fbi fbs fbt fbu fbx feb fee fef fei fes fet feu fex ffe fff ffi ffs fft ffu ffx fib fie fif fii fis fit fiu fix fsb fse fsf fsi fss fst fsu fsx ftb fte ftf fti fts ftt ftu ftx fub fue fuf fui fus fut fuu fux fxe fxi fxs fxt fxu fxx i-f ibb ibe ibf ibi ibs ibt ibu ibx ie- iee ief iei ies iet iex ifb ife iff ifi ifs ift ifu ifx iib iie iif iii iis iit iiu iix is- isb ise isf isi iss ist isu itb ite itf iti its itt itu itx iu- iub iue iui ius iut ixe ixi sbb sbe sbf sbi sbs sbt sbu sbx se- seb see sef sei ses set seu sex sfb sfe sff sfi sfs sft sfu sfx sib sie sif sii sis sit siu six ss- ssb sse ssf ssi sss sst ssu ssx stb ste stf sti sts stt stu stx sub sue suf sui sus sut suu sux sxi sxs sxt sxu t-x tbb tbe tbf tbi tbs tbt tbu te- teb tee tef tei tes tet teu tex tfb tfe tff tfi tfs tft tfu tfx tib tie tif tii tis tit tiu tix tsb tse tsf tsi tss tst tsu tsx ttb tte ttf tti tts ttt ttu ttx tub tue tuf tui tus tut tuu tux txe txf txi txs txt txu ubb ube ubf ubi ubs ubt ubu ubx ueb uee uef uei ues uet ufe uff ufi ufs uft ufu ufx uib uie uif uii uis uit uiu usb use usf usi uss ust usu usx utb ute utf uti uts utt utu utx uue uus uut uuu uxb uxf uxt uxu xbe xbx xee xes xet xeu xex xfe xfs xft xfx xie xii xis xit xiu xix xsb xsi xss xst xtf xti xts xtx xue xui xus xxi xxx