bbb bbd bbe bbo bbs bbt bdb bdd bde bdo bds bdt be- beb bed bee beo bes bet bob bod boe boo bos bot bsb bsd bse bso bss bst btb btd bte bto bts btt dbb dbd dbe dbo dbs dbt ddb ddd dde ddo dds ddt de- deb ded dee deo des det dob dod doe doo dos dot dsb dsd dse dso dss dst dtb dtd dte dto dts dtt ebb ebd ebe ebo ebs ebt ed- edb edd ede edo eds edt eeb eed eee eeo ees eet eo- eob eod eoe eoo eos eot es- esb esd ese eso ess est etb etd ete eto ets ett ob- obb obd obe obo obs obt odb odd ode odo ods odt oeb oed oee oeo oes oet oo- oob ood ooo oos oot os- osb osd ose oso oss ost ot- otb otd ote oto ots ott sbb sbd sbe sbo sbs sbt sdb sdd sde sdo sds sdt se- seb sed see seo ses set sob sod soe soo sos sot ss- ssb ssd sse sso sss sst stb std ste sto sts stt tbb tbd tbe tbo tbs tbt tdb tdd tde tdo tds tdt te- teb ted tee teo tes tet to- tob tod toe too tos tot tsb tsd tse tso tss tst ttb ttd tte tto tts ttt