-ic b-u bbb bbc bbi bbr bbt bbu bcb bcc bci bcr bct bcu bi- bib bic bii bir bit biu brb bri brr brt bru btb btc bti btr btt btu bub buc bui bur but buu c-- cbb cbc cbi cbr cbt cbu ccb ccc cci ccr cct ccu ci- cib cic cii cir cit ciu crb crc cri crr crt cru ctb ctc cti ctr ctt ctu cub cuc cui cur cut cuu ibb ibc ibi ibr ibt ibu icb icc ici icr ict icu iib iic iii iir iit iiu ir- irb irc iri irr irt iru itb itc iti itt itu iu- iub iuc iui iur iut rbb rbc rbi rbr rbt rbu rcb rcc rci rcr rct rcu rib ric rii rir rit rrb rrc rri rrr rrt rru rtb rtc rti rtr rtt rtu rub ruc rui rur rut ruu tbb tbc tbi tbr tbt tbu tcb tcc tci tcr tct tcu tib tic tii tir tit tiu trb trc tri trr trt tru ttb ttc tti ttr ttt ttu tub tuc tui tur tut tuu ubb ubc ubi ubr ubt ubu ucb ucc uci ucr uct ucu uib uic uii uir uit uiu ur- urb urc uri urr urt uru utb utc uti utr utt utu uuc uur uut uuu