a-a a-b a-i a-t a-z aaa aab aai aao aas aat aaz ab- aba abb abi abo abs abt abz ai- aia aib aii aio ais ait aiz aoa aob aoi aoo aos aot as- asa asb asi aso ass ast asz at- ata atb ati ato ats att atz az- aza azb azi azo azs azt azz baa bab bai bao bas bat baz bba bbb bbi bbo bbs bbt bi- bia bib bii bio bis bit biz boa bob boi boo bos bot boz bsa bsb bsi bso bss bst bta btb bti bto bts btt btz bza bzo bzs bzz ia- iaa iab iai iao ias iat iaz iba ibb ibi ibo ibs ibt ibz iia iib iii iio iis iit io- ioa iob ioi ioo ios iot is- isa isb isi iso iss ist ita itb iti ito its itt itz iza izi izo izz o-i oaa oab oai oao oas oat ob- oba obb obi obo obs obt oia oib oii oio ois oit oiz oo- ooa oob ooi ooo oos oot os- osa osb osi oso oss ost ot- ota otb oti oto ots ott otz oza ozo ozs ozt ozz saa sab sai sao sas sat saz sba sbb sbi sbo sbs sbt sia sib sii sio sis sit soa sob soi soo sos sot soz ss- ssa ssb ssi sso sss sst ssz sta stb sti sto sts stt stz sza szi taa tab tai tao tas tat taz tba tbb tbi tbo tbs tbt tbz tia tib tii tio tis tit tiz to- toa tob toi too tos tot toz tsa tsb tsi tso tss tst tta ttb tti tto tts ttt tza tzs zaa zab zai zao zas zat zaz zbb zbs zbt zia zib zio zis zit ziz zo- zoa zob zoi zoo zos zot zsa zsi zst zsz zta zzs zzt zzz