a-a a-b a-i aaa aab aaf aai aam aao aar aas ab- aba abb abf abi abm abo abr abs af- afa afb aff afi afm afo afr afs ai- aia aib aif aii aim aio air ais ama amb amf ami amm amo amr ams aoa aob aof aoi aom aoo aor aos ar- ara arb arf ari arm aro arr ars as- asa asb asf asi asm aso asr ass baa bab baf bai bam bao bar bas bba bbb bbf bbi bbm bbo bbr bbs bfa bfb bff bfi bfm bfo bfr bfs bi- bia bib bif bii bim bio bir bis bma bmb bmf bmi bmm bmo bmr bms boa bob bof boi bom boo bor bos bra brb brf bri brm bro brr brs bsa bsb bsf bsi bsm bso bsr bss faa fab faf fai fam fao far fas fba fbb fbf fbi fbm fbo fbr fbs ffa fff ffi ffm ffo ffr ffs fia fib fif fii fim fir fis fma fmb fmf fmi fmm fmo fmr fms foa fob fof foi fom foo for fos fra frb frf fri frm fro frr frs fsa fsb fsf fsi fsm fso fsr fss i-f ia- iaa iab iaf iai iam iao iar ias iba ibb ibf ibi ibm ibo ibr ibs ifa ifb iff ifi ifm ifo ifr ifs iia iib iif iii iim iio iir iis im- ima imb imf imi imm imo ims io- ioa iob iof ioi iom ioo ior ios ir- ira irb irf iri irm iro irr irs is- isa isb isf isi ism iso isr iss m-f m-o m-r maa mab maf mai mam mao mar mas mba mbb mbf mbi mbm mbo mbr mbs mfa mfb mff mfi mfm mfo mfr mfs mi- mia mib mif mii mim mio mir mis mma mmb mmf mmi mmm mmo mmr mms moa mob mof moi mom moo mor mos mra mrb mrf mri mrm mro mrr mrs msa msb msf msi msm mso msr mss o-i oaa oab oaf oai oam oao oar oas ob- oba obb obf obi obm obo obr obs of- ofa ofb off ofi ofm ofo ofr ofs oia oib oif oii oim oio oir ois om- oma omb omf omi omm omo omr oms oo- ooa oob oof ooi oom ooo oor oos or- ora orb orf ori orm oro orr ors os- osa osb osf osi osm oso osr oss ra- raa rab raf rai ram rao rar ras rba rbb rbf rbi rbm rbo rbr rbs rfa rfb rff rfi rfm rfo rfr rfs ria rib rif rii rim rio rir ris rma rmb rmf rmi rmm rmo rmr rms roa rob rof roi rom roo ror ros rra rrb rrf rri rrm rrr rrs rsa rsb rsf rsi rsm rso rsr rss saa sab saf sai sam sao sar sas sba sbb sbf sbi sbm sbo sbr sbs sfa sfb sff sfi sfm sfo sfr sfs sia sib sif sii sim sio sir sis sma smb smf smi smm smo smr sms soa sob sof soi som soo sor sos sr- sra srb srf sri srm sro srr srs ss- ssa ssb ssf ssi ssm sso ssr sss