a-a a-b a-i aaa aab aaf aag aai aan aao aas ab- aba abb abf abg abi abn abo abs af- afa afb aff afg afi afn afo afs ag- aga agb agf agg agi agn ago ags ai- aia aib aif aig aii ain aio ais an- ana anb anf ang ani ann ano ans aoa aob aof aog aoi aon aoo aos as- asa asb asf asg asi asn aso ass baa bab baf bag bai ban bao bas bba bbb bbf bbg bbi bbn bbo bbs bfa bfb bff bfg bfi bfn bfo bfs bga bgb bgf bgg bgi bgn bgo bgs bi- bia bib bif big bii bin bio bis bna bnb bnf bng bni bnn bno bns boa bob bof bog boi bon boo bos bsa bsb bsf bsg bsi bsn bso bss faa fab faf fag fai fan fao fas fba fbb fbf fbg fbi fbn fbo fbs ffa fff ffg ffi ffn ffo ffs fga fgb fgf fgg fgi fgn fgs fia fib fif fig fii fin fis fna fnb fnf fng fni fnn fns foa fob fof fog foi fon foo fos fsa fsb fsf fsg fsi fsn fso fss gaa gab gaf gag gai gan gao gas gba gbf gbg gbi gbn gbo gbs gfa gfb gff gfi gfo gfs gga ggb ggg ggi ggn ggo ggs gia gib gif gig gii gin gio gis gna gnb gnf gni gnn gno gns goa gob gof gog goi gon goo gos gsa gsb gsf gsg gsi gsn gso gss i-f ia- iaa iab iaf iag iai ian iao ias iba ibb ibf ibg ibi ibn ibo ibs ifa ifb iff ifg ifi ifn ifo ifs iga igb igf igg igi ign igo igs iia iib iif iii iin iio iis in- ina inb inf ing ini inn ino ins io- ioa iob iof iog ioi ion ioo ios is- isa isb isf isg isi isn iso iss n-i naa nab naf nag nai nan nao nas nba nbb nbf nbg nbi nbn nbo nbs nfa nfb nff nfi nfn nfo nfs nga ngb ngf ngg ngi ngn ngo ngs nia nib nif nig nii nin nio nis nna nnb nnf nng nni nnn nno nns no- noa nob nof nog noi non noo nos nsa nsb nsf nsg nsi nsn nso nss o-i oaa oab oaf oag oai oan oao oas ob- oba obb obf obg obi obn obo obs of- ofa ofb off ofg ofi ofn ofo ofs oga ogf ogg ogi ogn ogo ogs oia oib oif oii oin oio ois on- ona onb onf ong oni onn ono ons oo- ooa oob oof oog ooi oon ooo oos os- osa osb osf osg osi osn oso oss saa sab saf sag sai san sao sas sba sbb sbf sbg sbi sbn sbo sbs sfa sfb sff sfg sfi sfn sfo sfs sga sgb sgf sgg sgi sgn sgo sgs sia sib sif sig sii sin sio sis sna snb snf sng sni snn sno sns soa sob sof sog soi son soo sos ss- ssa ssb ssf ssg ssi ssn sso sss