bbb bbd bbo bbs bbt bby bdb bdd bdo bds bdt bdy bob bod boo bos bot boy bsb bsd bso bss bst bsy btb btd bto bts btt bty by- byd byo bys byt dbb dbd dbo dbs dbt dby ddb ddd ddo dds ddt ddy dob dod doo dos dot doy dsb dsd dso dss dst dsy dtb dtd dto dts dtt dty dy- dyb dyd dyo dys dyy ob- obb obd obo obs obt oby odb odd odo ods odt oo- oob ood ooo oos oot os- osb osd oso oss ost ot- otb otd oto ots ott oyd oyo oys sbb sbd sbo sbs sbt sby sdb sdd sdo sds sdt sdy sob sod soo sos sot soy ss- ssb ssd sso sss sst stb std sto sts stt sty sy- syb syd sys syt tbb tbd tbo tbs tbt tdb tdd tdo tds tdt tdy to- tob tod too tos tot toy tsb tsd tso tss tst tsy ttb ttd tto tts ttt tty tyd tyo tys tyt ybs yby ydo yds ydt ydy yob yod yoo yos yot yoy ysb yso yss yst ysy ytd yto yts ytt yyb yys yyt yyy