bbb bbg bbi bbr bbs bgb bgg bgi bgr bgs bi- bib big bii bir bis brb brg bri brr brs bsb bsg bsi bsr bss gbg gbi gbr gbs ggb ggg ggi ggr ggs gib gig gii gir gis grb grg gri grr grs gsb gsg gsi gsr gss ibb ibg ibi ibr ibs igb igg igi igr igs iib iii iir iis ir- irb irg iri irr irs is- isb isg isi isr iss rbb rbg rbi rbr rbs rgb rgg rgi rgr rgs rib rig rii rir ris rrb rrg rri rrr rrs rsb rsg rsi rsr rss sbb sbg sbi sbr sbs sgb sgg sgi sgr sgs sib sig sii sir sis sr- srb srg sri srr srs ss- ssb ssg ssi ssr sss