a-a a-b a-t aaa aab aad aao aas aat aax aay ab- aba abb abd abo abs abt abx aby ad- ada adb add ado ads adt adx ady aoa aob aod aoo aos aot aox as- asa asb asd aso ass ast asx asy at- ata atb atd ato ats att atx ax- axa axo axs axt axx ay- aya ayd ayo ays ayt ayx baa bab bad bao bas bat bax bay bba bbb bbd bbo bbs bbt bbx bby bda bdb bdd bdo bds bdt bdx bdy boa bob bod boo bos bot box boy bsa bsb bsd bso bss bst bsx bsy bta btb btd bto bts btt btx bty bxb bxd bxo bxx by- bya byd byo bys byt daa dab dad dao das dat dax day dba dbb dbd dbo dbs dbt dbx dby dda ddb ddd ddo dds ddt ddx ddy doa dob dod doo dos dot dox doy dsa dsb dsd dso dss dst dsx dsy dta dtb dtd dto dts dtt dtx dty dxd dxo dxs dxt dxx dy- dya dyb dyd dyo dys dyy oaa oab oad oao oas oat oax ob- oba obb obd obo obs obt obx oby oda odb odd odo ods odt oo- ooa oob ood ooo oos oot oox os- osa osb osd oso oss ost osx ot- ota otb otd oto ots ott ox- oxa oxb oxo oxt oxx oxy oya oyd oyo oys saa sab sad sao sas sat sax say sba sbb sbd sbo sbs sbt sbx sby sda sdb sdd sdo sds sdt sdy soa sob sod soo sos sot sox soy ss- ssa ssb ssd sso sss sst ssx sta stb std sto sts stt stx sty sxs sxt sy- sya syb syd sys syt syx t-x taa tab tad tao tas tat tax tay tba tbb tbd tbo tbs tbt tda tdb tdd tdo tds tdt tdx tdy to- toa tob tod too tos tot tox toy tsa tsb tsd tso tss tst tsx tsy tta ttb ttd tto tts ttt ttx tty txs txt tya tyd tyo tys tyt xaa xad xas xat xbx xda xdb xds xdt xoa xod xoo xos xot xox xsa xsb xss xst xts xtx xty xxo xxx xxy xyy yaa yab yad yao yas yat yax yay ybs yby yda ydo yds ydt ydy yob yod yoo yos yot yox yoy ysa ysb yso yss yst ysy yta ytd yto yts ytt yxa yxy yyb yys yyt yyy