-er -ic b-u bbb bbc bbe bbg bbi bbr bbu bcb bcc bce bcg bci bcr bcu be- beb bec bee beg bei ber beu bgb bgc bge bgg bgi bgr bgu bi- bib bic bie big bii bir biu brb bre brg bri brr bru bub buc bue bug bui bur buu c-- cbb cbc cbe cbg cbi cbr cbu ccb ccc cce ccg cci ccr ccu ce- ceb cec cee ceg cei cer ceu cgb cgc cge cgg cgi cgr cgu ci- cib cic cie cig cii cir ciu crb crc cre crg cri crr cru cub cuc cue cug cui cur cuu ebb ebc ebe ebg ebi ebr ebu ec- ecb ecc ece ecg eci ecr ecu eeb eec eee eeg eer egb egc ege egg egi egr egu eib eic eie eig eii eir eiu erb erc ere erg eri err eru eu- eub euc eue eug eui eur gbc gbe gbg gbi gbr gbu gcb gcc gce gcg gci gcr gcu ge- geb gec gee geg gei ger geu ggb ggc ggg ggi ggr ggu gib gic gie gig gii gir giu grb grc gre grg gri grr gru gu- gub guc gue gug gui gur guu ibb ibc ibe ibg ibi ibr ibu icb icc ice icg ici icr icu ie- iec iee ieg iei ier igb igc ige igg igi igr igu iib iic iie iii iir iiu ir- irb irc ire irg iri irr iru iu- iub iuc iue iug iui iur rbb rbc rbe rbg rbi rbr rbu rcb rcc rce rcg rci rcr rcu re- reb rec ree reg rei rer reu rgb rgc rge rgg rgi rgr rib ric rie rig rii rir rrb rrc rrg rri rrr rru rub ruc rue rug rui rur ruu ubb ubc ube ubg ubi ubr ubu ucb ucc uce ucg uci ucr ucu ueb uec uee ueg uei uer ugb ugc uge ugg ugi ugr ugu uib uic uie uig uii uir uiu ur- urb urc ure urg uri urr uru uuc uue uug uur uuu