b-p bbb bbi bbo bbp bbt bi- bib bii bio bip bit bob boi boo bop bot bpb bpi bpo bpp bpt btb bti bto btp btt ibb ibi ibo ibp ibt iib iii iio iip iit io- iob ioi ioo iop iot ipb ipi ipo ipp ipt itb iti ito itp itt o-i ob- obb obi obo obp obt oib oii oio oip oit oo- oob ooi ooo oop oot op- opb opi opo opp opt ot- otb oti oto otp ott p-p pbb pbi pbo pbp pbt pib pii pio pip pit pob poi poo pop pot ppb ppi ppo ppp ppt pt- ptb pti pto ptp ptt tbb tbi tbo tbp tbt tib tii tio tip tit to- tob toi too top tot tpb tpi tpo tpp tpt ttb tti tto ttp ttt