-er -ic b-u bbb bbc bbe bbg bbi bbr bbs bbu bcb bcc bce bcg bci bcr bcs bcu be- beb bec bee beg bei ber bes beu bgb bgc bge bgg bgi bgr bgs bgu bi- bib bic bie big bii bir bis biu brb bre brg bri brr brs bru bsb bsc bse bsg bsi bsr bss bsu bub buc bue bug bui bur bus buu c-- cbb cbc cbe cbg cbi cbr cbs cbu ccb ccc cce ccg cci ccr ccs ccu ce- ceb cec cee ceg cei cer ces ceu cgb cgc cge cgg cgi cgr cgs cgu ci- cib cic cie cig cii cir cis ciu crb crc cre crg cri crr crs cru csb csc cse csg csi csr css csu cub cuc cue cug cui cur cus cuu ebb ebc ebe ebg ebi ebr ebs ebu ec- ecb ecc ece ecg eci ecr ecs ecu eeb eec eee eeg eer ees egb egc ege egg egi egr egs egu eib eic eie eig eii eir eis eiu erb erc ere erg eri err ers eru es- esb esc ese esg esi esr ess esu eu- eub euc eue eug eui eur eus gbc gbe gbg gbi gbr gbs gbu gcb gcc gce gcg gci gcr gcs gcu ge- geb gec gee geg gei ger ges geu ggb ggc ggg ggi ggr ggs ggu gib gic gie gig gii gir gis giu grb grc gre grg gri grr grs gru gsb gsc gse gsg gsi gsr gss gsu gu- gub guc gue gug gui gur gus guu ibb ibc ibe ibg ibi ibr ibs ibu icb icc ice icg ici icr ics icu ie- iec iee ieg iei ier ies igb igc ige igg igi igr igs igu iib iic iie iii iir iis iiu ir- irb irc ire irg iri irr irs iru is- isb isc ise isg isi isr iss isu iu- iub iuc iue iug iui iur ius rbb rbc rbe rbg rbi rbr rbs rbu rcb rcc rce rcg rci rcr rcs rcu re- reb rec ree reg rei rer res reu rgb rgc rge rgg rgi rgr rgs rib ric rie rig rii rir ris rrb rrc rrg rri rrr rrs rru rsb rsc rse rsg rsi rsr rss rsu rub ruc rue rug rui rur rus ruu sbb sbc sbe sbg sbi sbr sbs sbu scb scc sce scg sci scr scs scu se- seb sec see seg sei ser ses seu sgb sgc sge sgg sgi sgr sgs sgu sib sic sie sig sii sir sis siu sr- srb src sre srg sri srr srs ss- ssb ssc sse ssg ssi ssr sss ssu sub suc sue sug sui sur sus suu ubb ubc ube ubg ubi ubr ubs ubu ucb ucc uce ucg uci ucr ucs ucu ueb uec uee ueg uei uer ues ugb ugc uge ugg ugi ugr ugs ugu uib uic uie uig uii uir uis uiu ur- urb urc ure urg uri urr urs uru usb usc use usg usi usr uss usu uuc uue uug uur uus uuu