a-a aaa aaf aag aao aap aas af- afa aff afg afo afp afs ag- aga agf agg ago agp ags aoa aof aog aoo aop aos ap- apa apf apg apo app aps as- asa asf asg aso asp ass faa faf fag fao fap fas ffa fff ffg ffo ffp ffs fga fgf fgg fgp fgs foa fof fog foo fop fos fpa fpg fpo fpp fps fsa fsf fsg fso fsp fss g-p gaa gaf gag gao gap gas gfa gff gfo gfp gfs gga ggg ggo ggp ggs goa gof gog goo gop gos gpa gpf gpg gpo gpp gps gsa gsf gsg gso gsp gss oaa oaf oag oao oap oas of- ofa off ofg ofo ofp ofs oga ogf ogg ogo ogp ogs oo- ooa oof oog ooo oop oos op- opa opf opg opo opp ops os- osa osf osg oso osp oss p-p paa paf pag pao pap pas pfa pff pfg pfo pfp pfs pga pgf pgg pgo pgp pgs poa pof pog poo pop pos ppa ppf ppg ppo ppp pps ps- psa psf psg pso psp pss saa saf sag sao sap sas sfa sff sfg sfo sfp sfs sga sgf sgg sgo sgp sgs soa sof sog soo sop sos spa spf spg spo spp sps ss- ssa ssf ssg sso ssp sss