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DescriptionThefarmhasmanyhillsuponwhichFarmerJohnwouldliketoplaceguardstoensurethesafetyofhisvaluablemilk-cows.Hewondershowmanyguardshewillneedifhewishestoputoneontopofeachhill.Hehasamapsuppliedasamatrixofintegers;thematrixhasN(1<N<=700)rowsandM(1<M<=700)columns.EachmemberofthematrixisanaltitudeH_ij(0<=H_ij<=10,000).Helphimdeterminethenumberofhilltopsonthemap.Ahill...
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DescriptionThepasturecontainsasmall,contiguousgroveoftreesthathasno'holes'inthemiddleoftheit.Bessiewonders:howfarisittowalkaroundthatgroveandgetbacktomystartingposition?She'sjustsurethereisawaytodoitbygoingfromherstartlocationtosuccessivelocationsbywalkinghorizontally,vertically,ordiagonallyandcountingeachmoveasasinglestep.Justlookingatit,shedoesn'tthinkyoucouldpass'through'thegroveonatrickyd...

Manystudentsliveinadormitory.Adormitoryisawholenewworldoffunnyamusementsandpossibilitiesbutitdoeshaveitsdrawbacks.Thereisonlyoneshowerandtherearemultiplestudentswhowishtohaveashowerinthemorning.That'swhyeverymorningthereisalineoffivepeopleinfrontofthedormitoryshowerdoor.Assoonastheshoweropens,thefirstpersonfromthelineenterstheshower.Afterawhilethefirstpersonleavestheshowerandthenextpersonent...
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