a-a aaa aaf aag aan aao aas af- afa aff afg afn afo afs ag- aga agf agg agn ago ags an- ana anf ang ann ano ans aoa aof aog aon aoo aos as- asa asf asg asn aso ass faa faf fag fan fao fas ffa fff ffg ffn ffo ffs fga fgf fgg fgn fgs fna fnf fng fnn fns foa fof fog fon foo fos fsa fsf fsg fsn fso fss gaa gaf gag gan gao gas gfa gff gfo gfs gga ggg ggn ggo ggs gna gnf gnn gno gns goa gof gog gon goo gos gsa gsf gsg gsn gso gss naa naf nag nan nao nas nfa nff nfn nfo nfs nga ngf ngg ngn ngo ngs nna nnf nng nnn nno nns no- noa nof nog non noo nos nsa nsf nsg nsn nso nss oaa oaf oag oan oao oas of- ofa off ofg ofn ofo ofs oga ogf ogg ogn ogo ogs on- ona onf ong onn ono ons oo- ooa oof oog oon ooo oos os- osa osf osg osn oso oss saa saf sag san sao sas sfa sff sfg sfn sfo sfs sga sgf sgg sgn sgo sgs sna snf sng snn sno sns soa sof sog son soo sos ss- ssa ssf ssg ssn sso sss