-er a-a a-b a-i aaa aab aad aae aag aai aar aas ab- aba abb abd abe abg abi abr abs ad- ada adb add ade adg adi adr ads aea aeb aed aee aeg aei aer aes ag- aga agb agd age agg agi agr ags ai- aia aib aid aie aig aii air ais ar- ara arb ard are arg ari arr ars as- asa asb asd ase asg asi asr ass baa bab bad bae bag bai bar bas bba bbb bbd bbe bbg bbi bbr bbs bda bdb bdd bde bdg bdi bdr bds be- bea beb bed bee beg bei ber bes bga bgb bgd bge bgg bgi bgr bgs bi- bia bib bid bie big bii bir bis bra brb brd bre brg bri brr brs bsa bsb bsd bse bsg bsi bsr bss daa dab dad dae dag dai dar das dba dbb dbd dbe dbg dbi dbr dbs dda ddb ddd dde ddg ddi ddr dds de- dea deb ded dee deg dei der des dga dgd dge dgg dgi dgr dgs di- dia dib did die dig dii dir dis dra drb drd dre drg dri drr drs dsa dsb dsd dse dsg dsi dsr dss eaa eab ead eae eag eai ear eas eba ebb ebd ebe ebg ebi ebr ebs ed- eda edb edd ede edg edi edr eds eea eeb eed eee eeg eer ees ega egb egd ege egg egi egr egs eia eib eid eie eig eii eir eis era erb erd ere erg eri err ers es- esa esb esd ese esg esi esr ess g-d gaa gab gad gae gag gai gar gas gba gbd gbe gbg gbi gbr gbs gda gdb gdd gde gdi gdr gds ge- gea geb ged gee geg gei ger ges gga ggb ggd ggg ggi ggr ggs gia gib gid gie gig gii gir gis gra grb grd gre grg gri grr grs gsa gsb gsd gse gsg gsi gsr gss i-d ia- iaa iab iad iae iag iai iar ias iba ibb ibd ibe ibg ibi ibr ibs ida idb idd ide idg idi idr ids ie- iea ied iee ieg iei ier ies iga igb igd ige igg igi igr igs iia iib iid iie iii iir iis ir- ira irb ird ire irg iri irr irs is- isa isb isd ise isg isi isr iss ra- raa rab rad rae rag rai rar ras rba rbb rbd rbe rbg rbi rbr rbs rda rdb rdd rde rdg rdi rdr rds re- rea reb red ree reg rei rer res rga rgb rgd rge rgg rgi rgr rgs ria rib rid rie rig rii rir ris rra rrb rrd rrg rri rrr rrs rsa rsb rsd rse rsg rsi rsr rss saa sab sad sae sag sai sar sas sba sbb sbd sbe sbg sbi sbr sbs sda sdb sdd sde sdg sdi sdr sds se- sea seb sed see seg sei ser ses sga sgb sgd sge sgg sgi sgr sgs sia sib sid sie sig sii sir sis sr- sra srb srd sre srg sri srr srs ss- ssa ssb ssd sse ssg ssi ssr sss