-er a-a a-b aaa aab aad aae aaf aan aar aas ab- aba abb abd abe abf abn abr abs ad- ada adb add ade adf adn adr ads aea aeb aed aee aef aen aer aes af- afa afb afd afe aff afn afr afs an- ana anb and ane anf ann anr ans ar- ara arb ard are arf arn arr ars as- asa asb asd ase asf asn asr ass baa bab bad bae baf ban bar bas bba bbb bbd bbe bbf bbn bbr bbs bda bdb bdd bde bdf bdr bds be- bea beb bed bee bef ben ber bes bfa bfb bfd bfe bff bfn bfr bfs bna bnb bnd bne bnf bnn bnr bns bra brb brd bre brf brn brr brs bsa bsb bsd bse bsf bsn bsr bss daa dab dad dae daf dan dar das dba dbb dbd dbe dbf dbn dbr dbs dda ddb ddd dde ddf ddn ddr dds de- dea deb ded dee def den der des dfa dfb dfd dfe dff dfn dfr dfs dna dnb dnd dne dnf dnn dnr dns dra drb drd dre drn drr drs dsa dsb dsd dse dsf dsn dsr dss eaa eab ead eae eaf ean ear eas eba ebb ebd ebe ebf ebn ebr ebs ed- eda edb edd ede edf edn edr eds eea eeb eed eee eef een eer ees ef- efa efb efd efe eff efr efs en- ena enb end ene enf enn enr ens era erb erd ere erf ern err ers es- esa esb esd ese esf esn esr ess faa fab fad fae faf fan far fas fba fbb fbd fbe fbf fbn fbr fbs fda fdb fdd fde fdf fdn fdr fds fea feb fed fee fef fen fer fes ffa ffd ffe fff ffn ffr ffs fna fnb fnd fne fnf fnn fnr fns fra frb frd fre frf frn frr frs fsa fsb fsd fse fsf fsn fsr fss naa nab nad nae naf nan nar nas nba nbb nbd nbe nbf nbn nbr nbs nda ndb ndd nde ndf ndn ndr nds ne- nea neb ned nee nef nen ner nes nfa nfb nfd nfe nff nfn nfr nfs nna nnb nne nnf nnn nns nra nrb nrd nre nrf nrn nrr nrs nsa nsb nsd nse nsf nsn nsr nss ra- raa rab rad rae raf ran rar ras rba rbb rbd rbe rbf rbn rbr rbs rda rdb rdd rde rdf rdn rdr rds re- rea reb red ree ref ren rer res rfa rfb rfd rfe rff rfn rfr rfs rna rnb rnd rnn rnr rns rra rrb rrd rrf rrn rrr rrs rsa rsb rsd rse rsf rsn rsr rss saa sab sad sae saf san sar sas sba sbb sbd sbe sbf sbn sbr sbs sda sdb sdd sde sdf sdn sdr sds se- sea seb sed see sef sen ser ses sfa sfb sfd sfe sff sfn sfr sfs sna snb snd sne snf snn snr sns sr- sra srb srd sre srf srn srr srs ss- ssa ssb ssd sse ssf ssn ssr sss