bbb bbf bbi bbr bbs bby bfb bff bfi bfr bfs bfy bi- bib bif bii bir bis biy brb brf bri brr brs bry bsb bsf bsi bsr bss bsy by- byf byi byr bys fbb fbf fbi fbr fbs fff ffi ffr ffs ffy fib fif fii fir fis frb frf fri frr frs fry fsb fsf fsi fsr fss fy- fyb fyi i-f ibb ibf ibi ibr ibs iby ifb iff ifi ifr ifs ify iib iif iii iir iis ir- irb irf iri irr irs iry is- isb isf isi isr iss isy iyr iys iyy rbb rbf rbi rbr rbs rfb rff rfi rfr rfs rib rif rii rir ris riy rrb rrf rri rrr rrs rsb rsf rsi rsr rss ry- ryf ryr rys ryy sbb sbf sbi sbr sbs sby sfb sff sfi sfr sfs sib sif sii sir sis sr- srb srf sri srr srs sry ss- ssb ssf ssi ssr sss sy- syb syi syr sys ybf ybi ybr ybs yby yff yfr yfs yif yii yir yis yrf yrs ysb ysi ysr yss ysy yyb yyf yys yyy