-ic bbb bbc bbf bbi bbo bbr bbt bcb bcc bcf bci bco bcr bct bfb bfc bff bfi bfo bfr bft bi- bib bic bif bii bio bir bit bob boc bof boi boo bor bot brb brf bri bro brr brt btb btc btf bti bto btr btt c-- cbb cbc cbf cbi cbo cbr cbt ccb ccc ccf cci cco ccr cct cfb cfc cff cfi cfo cfr cft ci- cib cic cif cii cio cir cit co- cob coc cof coi coo cor cot crb crc crf cri cro crr crt ctb ctc ctf cti cto ctr ctt fbb fbc fbf fbi fbo fbr fbt fcb fcc fcf fci fco fcr fct ffc fff ffi ffo ffr fft fib fic fif fii fir fit fob foc fof foi foo for fot frb frc frf fri fro frr frt ftb ftc ftf fti fto ftr ftt i-f ibb ibc ibf ibi ibo ibr ibt icb icc icf ici ico icr ict ifb ifc iff ifi ifo ifr ift iib iic iif iii iio iir iit io- iob ioc iof ioi ioo ior iot ir- irb irc irf iri iro irr irt itb itc itf iti ito itt o-i ob- obb obc obf obi obo obr obt oc- ocb occ ocf oci oco ocr oct of- ofb ofc off ofi ofo ofr oft oib oic oif oii oio oir oit oo- oob ooc oof ooi ooo oor oot or- orb orc orf ori oro orr ort ot- otb otc otf oti oto otr ott rbb rbc rbf rbi rbo rbr rbt rcb rcc rcf rci rco rcr rct rfb rfc rff rfi rfo rfr rft rib ric rif rii rio rir rit rob roc rof roi roo ror rot rrb rrc rrf rri rrr rrt rtb rtc rtf rti rto rtr rtt tbb tbc tbf tbi tbo tbr tbt tcb tcc tcf tci tco tcr tct tfb tfc tff tfi tfo tfr tft tib tic tif tii tio tir tit to- tob toc tof toi too tor tot trb trc trf tri tro trr trt ttb ttc ttf tti tto ttr ttt