-er -ic bbb bbc bbe bbg bbi bbr bcb bcc bce bcg bci bcr be- beb bec bee beg bei ber bgb bgc bge bgg bgi bgr bi- bib bic bie big bii bir brb bre brg bri brr c-- cbb cbc cbe cbg cbi cbr ccb ccc cce ccg cci ccr ce- ceb cec cee ceg cei cer cgb cgc cge cgg cgi cgr ci- cib cic cie cig cii cir crb crc cre crg cri crr ebb ebc ebe ebg ebi ebr ec- ecb ecc ece ecg eci ecr eeb eec eee eeg eer egb egc ege egg egi egr eib eic eie eig eii eir erb erc ere erg eri err gbc gbe gbg gbi gbr gcb gcc gce gcg gci gcr ge- geb gec gee geg gei ger ggb ggc ggg ggi ggr gib gic gie gig gii gir grb grc gre grg gri grr ibb ibc ibe ibg ibi ibr icb icc ice icg ici icr ie- iec iee ieg iei ier igb igc ige igg igi igr iib iic iie iii iir ir- irb irc ire irg iri irr rbb rbc rbe rbg rbi rbr rcb rcc rce rcg rci rcr re- reb rec ree reg rei rer rgb rgc rge rgg rgi rgr rib ric rie rig rii rir rrb rrc rrg rri rrr