b-u bbb bbd bbf bbn bbo bbr bbs bbt bbu bdb bdd bdf bdo bdr bds bdt bdu bfb bfd bff bfn bfo bfr bfs bft bfu bnb bnd bnf bnn bno bnr bns bnt bnu bob bod bof bon boo bor bos bot bou brb brd brf brn bro brr brs brt bru bsb bsd bsf bsn bso bsr bss bst bsu btb btd btf btn bto btr bts btt btu bub bud buf bun buo bur bus but buu dbb dbd dbf dbn dbo dbr dbs dbt dbu ddb ddd ddf ddn ddo ddr dds ddt ddu dfb dfd dff dfn dfo dfr dfs dft dfu dnb dnd dnf dnn dno dnr dns dnt dob dod dof don doo dor dos dot dou drb drd drn dro drr drs drt dru dsb dsd dsf dsn dso dsr dss dst dsu dtb dtd dtf dtn dto dtr dts dtt dtu dub dud duf dun duo dur dus dut fbb fbd fbf fbn fbo fbr fbs fbt fbu fdb fdd fdf fdn fdo fdr fds fdt fdu ffd fff ffn ffo ffr ffs fft ffu fnb fnd fnf fnn fnr fns fnt fnu fob fof fon foo for fos fot fou frb frd frf frn fro frr frs frt fru fsb fsd fsf fsn fso fsr fss fst fsu ftb ftd ftf ftn fto ftr fts ftt ftu fub fud fuf fun fuo fur fus fut fuu nbb nbd nbf nbn nbo nbr nbs nbt nbu ndb ndd ndf ndn ndo ndr nds ndt ndu nfb nfd nff nfn nfo nfr nfs nft nfu nnb nnf nnn nno nns nnt nnu no- nob nod nof non noo nor nos not nou nrb nrd nrf nrn nro nrr nrs nrt nru nsb nsd nsf nsn nso nsr nss nst nsu ntb ntd ntf ntn nto ntr nts ntt ntu nub nud nun nuo nur nus nut nuu ob- obb obd obf obn obo obr obs obt obu odb odd odf odn odo odr ods odt odu of- ofb ofd off ofn ofo ofr ofs oft ofu on- onb ond onf onn ono onr ons ont onu oo- oob ood oof oon ooo oor oos oot or- orb ord orf orn oro orr ors ort oru os- osb osd osf osn oso osr oss ost osu ot- otb otd otf otn oto otr ots ott otu ou- oud ouf oun ouo our ous out rbb rbd rbf rbn rbo rbr rbs rbt rbu rdb rdd rdf rdn rdo rdr rds rdt rdu rfb rfd rff rfn rfo rfr rfs rft rfu rnb rnd rnn rno rnr rns rnt rnu rob rod rof ron roo ror ros rot rou rrb rrd rrf rrn rrr rrs rrt rru rsb rsd rsf rsn rso rsr rss rst rsu rtb rtd rtf rtn rto rtr rts rtt rtu rub rud ruf run ruo rur rus rut ruu sbb sbd sbf sbn sbo sbr sbs sbt sbu sdb sdd sdf sdn sdo sdr sds sdt sdu sfb sfd sff sfn sfo sfr sfs sft sfu snb snd snf snn sno snr sns snt snu sob sod sof son soo sor sos sot sou sr- srb srd srf srn sro srr srs srt ss- ssb ssd ssf ssn sso ssr sss sst ssu stb std stf stn sto str sts stt stu sub sud suf sun suo sur sus sut suu tbb tbd tbf tbn tbo tbr tbs tbt tbu tdb tdd tdf tdn tdo tdr tds tdt tdu tfb tfd tff tfn tfo tfr tfs tft tfu tnb tnd tnf tnn tno tnr tns tnt to- tob tod tof ton too tor tos tot tou trb trd trf trn tro trr trs trt tru tsb tsd tsf tsn tso tsr tss tst tsu ttb ttd ttf ttn tto ttr tts ttt ttu tub tud tuf tun tuo tur tus tut tuu ubb ubf ubn ubo ubr ubs ubt ubu udb udd udf udn udo udr uds udt udu ufd uff ufn ufo ufr ufs uft ufu un- unb und unf unn uno unr uns unt unu uob uod uon uoo uor uos uot ur- urb urd urf urn uro urr urs urt uru usb usd usf usn uso usr uss ust usu utb utd utf utn uto utr uts utt utu uun uur uus uut uuu