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ddirre ridrde irdrde rdirde drirde idrrde dirrde rirdde irrdde rridde rridde irrdde rirdde rdride drride rrdide rrdide drride rdride idrrde dirrde irdrde ridrde drirde rdirde ridrde irdrde rdirde drirde idrrde dirrde rirdde irrdde rridde rridde irrdde rirdde rdride drride rrdide rrdide drride rdride idrrde dirrde irdrde ridrde drirde rdirde rddrie drdrie rddrie drdrie ddrrie ddrrie rdrdie drrdie rrddie rrddie drrdie rdrdie rdrdie drrdie rrddie rrddie drrdie rdrdie ddrrie ddrrie drdrie rddrie drdrie rddrie iddrre didrre iddrre didrre ddirre ddirre idrdre dirdre irddre riddre dridre rdidre idrdre dirdre irddre riddre dridre rdidre ddrire ddrire drdire rddire drdire rddire riderd irderd rdierd drierd idrerd direrd riedrd iredrd reidrd eridrd ierdrd eirdrd rdeird dreird redird erdird derird edrird iderrd dierrd iedrrd eidrrd deirrd edirrd ridred irdred rdired drired idrred dirred rirded irrded rrided rrided irrded rirded rdried drried rrdied rrdied drried rdried idrred dirred irdred ridred drired rdired rierdd irerdd reirdd erirdd ierrdd eirrdd riredd irredd rriedd rriedd irredd riredd reridd erridd rreidd rreidd erridd reridd ierrdd eirrdd irerdd rierdd erirdd reirdd rderid drerid redrid erdrid derrid edrrid rdreid drreid rrdeid rrdeid drreid rdreid rerdid errdid rredid rredid errdid rerdid derrid edrrid drerid rderid erdrid redrid iderrd dierrd iedrrd eidrrd deirrd edirrd idrerd direrd irderd riderd drierd rdierd ierdrd eirdrd iredrd riedrd eridrd reidrd derird edrird dreird rdeird erdird redird riderd irderd rdierd drierd idrerd direrd riedrd iredrd reidrd eridrd ierdrd eirdrd rdeird dreird redird erdird derird edrird iderrd dierrd iedrrd eidrrd deirrd edirrd ridred irdred rdired drired idrred dirred rirded irrded rrided rrided irrded rirded rdried drried rrdied rrdied drried rdried idrred dirred irdred ridred drired rdired rierdd irerdd reirdd erirdd ierrdd eirrdd riredd irredd rriedd rriedd irredd riredd reridd erridd rreidd rreidd erridd reridd ierrdd eirrdd irerdd rierdd erirdd reirdd rderid drerid redrid erdrid derrid edrrid rdreid drreid rrdeid rrdeid drreid rdreid rerdid errdid rredid rredid errdid rerdid derrid edrrid drerid rderid erdrid redrid iderrd dierrd iedrrd eidrrd deirrd edirrd idrerd direrd irderd riderd drierd rdierd ierdrd eirdrd iredrd riedrd eridrd reidrd derird edrird dreird rdeird erdird redird rdderi drderi rdderi drderi ddreri ddreri rdedri dredri reddri erddri derdri edrdri rdedri dredri reddri erddri derdri edrdri dderri dderri dedrri eddrri dedrri eddrri rddrei drdrei rddrei drdrei ddrrei ddrrei rdrdei drrdei rrddei rrddei drrdei rdrdei rdrdei drrdei rrddei rrddei drrdei rdrdei ddrrei ddrrei drdrei rddrei drdrei rddrei rderdi drerdi redrdi erdrdi derrdi edrrdi rdredi drredi rrdedi rrdedi drredi rdredi rerddi errddi rreddi rreddi errddi rerddi derrdi edrrdi drerdi rderdi erdrdi redrdi rderdi drerdi redrdi erdrdi derrdi edrrdi rdredi drredi rrdedi rrdedi drredi rdredi rerddi errddi rreddi rreddi errddi rerddi derrdi edrrdi drerdi rderdi erdrdi redrdi dderri dderri dedrri eddrri dedrri eddrri ddreri ddreri drderi rdderi drderi rdderi derdri edrdri dredri rdedri erddri reddri derdri edrdri dredri rdedri erddri reddri idderr diderr idderr diderr ddierr ddierr idedrr diedrr ieddrr eiddrr deidrr edidrr idedrr diedrr ieddrr eiddrr deidrr edidrr ddeirr ddeirr dedirr eddirr dedirr eddirr iddrer didrer iddrer didrer ddirer ddirer idrder dirder irdder ridder drider rdider idrder dirder irdder ridder drider rdider ddrier ddrier drdier rddier drdier rddier iderdr dierdr iedrdr eidrdr deirdr edirdr idredr diredr irdedr ridedr driedr rdiedr ierddr eirddr ireddr rieddr eriddr reiddr deridr edridr dreidr rdeidr erdidr redidr iderdr dierdr iedrdr eidrdr deirdr edirdr idredr diredr irdedr ridedr driedr rdiedr ierddr eirddr ireddr rieddr eriddr reiddr deridr edridr dreidr rdeidr erdidr redidr dderir dderir dedrir eddrir dedrir eddrir ddreir ddreir drdeir rddeir drdeir rddeir derdir edrdir dredir rdedir erddir reddir derdir edrdir dredir rdedir erddir reddir
Note: these 'words' (valid or invalid) are all the permutations of the word ridder. These words are obtained by scrambling the letters in ridder.