bbb bbf bbi bbo bbr bbs bbt bfb bff bfi bfo bfr bfs bft bi- bib bif bii bio bir bis bit bob bof boi boo bor bos bot brb brf bri bro brr brs brt bsb bsf bsi bso bsr bss bst btb btf bti bto btr bts btt fbb fbf fbi fbo fbr fbs fbt fff ffi ffo ffr ffs fft fib fif fii fir fis fit fob fof foi foo for fos fot frb frf fri fro frr frs frt fsb fsf fsi fso fsr fss fst ftb ftf fti fto ftr fts ftt i-f ibb ibf ibi ibo ibr ibs ibt ifb iff ifi ifo ifr ifs ift iib iif iii iio iir iis iit io- iob iof ioi ioo ior ios iot ir- irb irf iri iro irr irs irt is- isb isf isi iso isr iss ist itb itf iti ito its itt o-i ob- obb obf obi obo obr obs obt of- ofb off ofi ofo ofr ofs oft oib oif oii oio oir ois oit oo- oob oof ooi ooo oor oos oot or- orb orf ori oro orr ors ort os- osb osf osi oso osr oss ost ot- otb otf oti oto otr ots ott rbb rbf rbi rbo rbr rbs rbt rfb rff rfi rfo rfr rfs rft rib rif rii rio rir ris rit rob rof roi roo ror ros rot rrb rrf rri rrr rrs rrt rsb rsf rsi rso rsr rss rst rtb rtf rti rto rtr rts rtt sbb sbf sbi sbo sbr sbs sbt sfb sff sfi sfo sfr sfs sft sib sif sii sio sir sis sit sob sof soi soo sor sos sot sr- srb srf sri sro srr srs srt ss- ssb ssf ssi sso ssr sss sst stb stf sti sto str sts stt tbb tbf tbi tbo tbr tbs tbt tfb tff tfi tfo tfr tfs tft tib tif tii tio tir tis tit to- tob tof toi too tor tos tot trb trf tri tro trr trs trt tsb tsf tsi tso tsr tss tst ttb ttf tti tto ttr tts ttt