[ZJOI2008]树的统计Count

题目大意：

给出一棵树，点上有点权

有两种询问，询问两点之间树链上的点权和，询问两点之间树链上最大点权

点数<=30000，询问树<=200000

最裸的动态树，操作少，维护的值简单

//Lib #include<cstdio> #include<cstring> #include<cstdlib> #include<cmath> #include<ctime> #include<iostream> #include<algorithm> #include<vector> #include<string> #include<queue> using namespace std; //Macro #define rep(i,a,b) for(int i=a,tt=b;i<=tt;++i) #define rrep(i,a,b) for(int i=a,tt=b;i>=tt;--i) #define erep(i,e,x) for(int i=x;i;i=e[i].next) #define irep(i,x) for(__typedef(x.begin()) i=x.begin();i!=x.end();i++) #define read() (strtol(ipos,&ipos,10)) #define sqr(x) ((x)*(x)) #define pb push_back #define PS system("pause"); typedef long long ll; typedef pair<int,int> pii; const int oo=100000000; const double inf=1e20; const double eps=1e-6; string name="",in=".in",out=".out"; //Var struct E { int next,node; }e[60008]; struct T { int LC,RC,KEY,SUM,MAX,FA; #define lc(x) tree[x].LC #define rc(x) tree[x].RC #define key(x) tree[x].KEY #define sum(x) tree[x].SUM #define Max(x) tree[x].MAX #define fa(x) tree[x].FA }tree[30008]; int tot,n,Q,w[30008],h[30008]; bool vis[30008]; inline void add(int a,int b){e[++tot].next=h[a];e[tot].node=b;h[a]=tot;} inline bool isRoot(int x){return (lc(fa(x))!=x)&&(rc(fa(x))!=x);} void Update(int x) { sum(x)=sum(lc(x))+sum(rc(x))+key(x); Max(x)=max(max(Max(lc(x)),Max(rc(x))),key(x)); }

inline void Zig(int x)

{int y=fa(x),z=fa(y);if(lc(z)==y)lc(z)=x;else if(rc(z)==y)rc(z)=x;fa(x)=z;fa(rc(x))=y;lc(y)=rc(x);rc(x)=y;fa(y)=x;Update(y);}inline void Zag(int x){int y=fa(x),z=fa(y);if(lc(z)==y)lc(z)=x;else if(rc(z)==y) rc(z)=x;fa(x)=z;fa(lc(x))=y;rc(y)=lc(x);lc(x)=y;fa(y)=x;Update(y);}void Splay(int x){for(int y,z;!isRoot(x);){y=fa(x);z=fa(y);if(isRoot(y))if(lc(y)==x)Zig(x);else Zag(x);elseif(lc(z)==y)if(lc(y)==x)Zig(y),Zig(x);else Zag(x),Zig(x);elseif(lc(y)==x)Zig(x),Zag(x);else Zag(y),Zag(x);}Update(x);}void DFS(int u,int f){key(u)=w[u];erep(i,e,h[u])if(e[i].node!=f)DFS(e[i].node,u),fa(e[i].node)=u;}void Init(){int a,b;scanf("%d",&n);rep(i,1,n-1){scanf("%d%d",&a,&b);add(a,b);add(b,a);}rep(i,1,n)scanf("%d",w+i);key(0)=Max(0)=-oo;DFS(1,0);}inline void Expose(int x){int y;for(y=0;x;x=fa(x)){Splay(x);rc(x)=y;Update(x);y=x;}}inline void Change(int x,int y){key(x)=y;Splay(x);}inline int Qmax(int x,int y){Expose(y);for(y=0;x;x=fa(x)){Splay(x);if(!fa(x))return max(key(x),max(Max(rc(x)),Max(y)));rc(x)=y;Update(x);y=x;}}inline int Qsum(int x,int y){Expose(y);for(y=0;x;x=fa(x)){Splay(x);if(!fa(x))return sum(rc(x))+key(x)+sum(y);rc(x)=y;Update(x);y=x;}}void Work(){char ch[10];int a,b;scanf("%d",&Q);rep(i,1,Q){scanf("%s%d%d",ch,&a,&b);if(ch[0]=='C')Change(a,b);else{if(ch[1]=='M')printf("%d\n",Qmax(a,b));else printf("%d\n",Qsum(a,b));}}}int main(){//freopen((name+in).c_str(),"r",stdin);//freopen((name+out).c_str(),"w",stdout);Init();Work();return 0;}