ProblemDescriptionYouaregivenatreewithNnodeswhicharenumberedbyintegers1..N.Eachnodeisassociatedwithanintegerastheweight.YourtaskistodealwithMoperationsof4types:1.Deleteanedge(x,y)fromthetree,andthenaddanewedge(a,b).Weensurethatitstillconstitutesatreeafteraddingthenewedge.2.Giventwonodesaandbinthetree,changetheweightsofallthenodesonthepathconnectingnodeaandb(includingnodeaandb)toaparticu...
ProblemDescriptionWehavemetsomanyproblemsonthetree,sotodaywewillhaveaqueryproblemonasetoftrees.ThereareNnodes,eachnodewillhaveauniqueweightWi.Wewillhavefourkindsofoperationsonitandyoushouldsolvethemefficiently.Wishyouhavefun! InputTherearemultipletestcasesinourdataset.Foreachcase,thefirstlinecontainsonlyoneintegerN.(1≤N≤300000)ThenextN‐1lineseachcontainstwointegersx,ywhichme...
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