dddd ddss ddts dfds dfdt dfrf dfri dftr dfts didi dids dif- diff difs diii diis dird dirr dirs dirt dis- disd disi diss dist diti dits ditt drif drit drrs dsdr dsif dsri dsrr dssi dsst dsts dtss fdst fdti ffff ffii ffrr ffss fftf fidf fids fiff fifi fift fiii firs fisd fisi fiss fist fiti fits fitt frid fris frit frst fsfi fssf ftdi ftii ftrs ftsr idid idir idis idrf idsf idss idts ifid ifis ifit ifrf ifri iiii iiis iiit iirs iisd iisi iisr iist iitr iitt irds iri- irid iris irri irrs irsf irtf irti irts isds isis isit isri issf issi issr isss istd isti istr ists itif itis itrf itri itrs itsf itsi ittf rfdi rfds rfid ridd ridi rids riff rifs rift riif riis riri rirs risd risi riss rist riti rits ritt rrif rrrr rsdd rsds rsid rsis rsts rtdt rtss rtts s-ii sdds sdif sdrs sdsf sdss sfss sfts sidd sidi sidr sids siff sifr sift siit sirf siri sirr sirs sirt sisd sisi siss sist sit- sitd siti sits sitt srfi sris srsd srtr ssdd ssdf ssid ssis ssit ssri ssrs sssf sssi ssss sstd ssts stds stid stif stir stis stit strd stri strs stsf stsi stss sttd sttr tdff tdis tdri tdss tfrs tfsd tfsi tfss tidd tids tiff tift tiit tird tiri tirr tirs tisi tiss tist titi tits titt trfd trfr tri- trif tris trit trsd trsi trst trtr tsid tsis tssf tssi tssr tsst tsts ttff ttss tttt