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| # include<bits/stdc++.h>
using namespace std;
typedef long long int LL;
const int INF = (~(1<<31));
const int N = 30000+7;
const double eps = 1e-7;
inline int read(){
int x=0,f=1;char ch = getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while('0'<=ch&&ch<='9'){x=(x<<3)+(x<<1)+ch-'0';ch=getchar();}
return x*f;
}
inline int gmax(int &x,int y){if(y>x)x=y;}
inline int gmin(int &x,int y){if(y<x)x=y;}
inline int mmax(int x,int y){if(y>x)x=y;return x; }
inline int mmin(int x,int y){if(y<x)x=y;return x; }
/****************************************************/
int w[N],n;
vector<int >G[N];
/***
tree cut
*/
int dep[N],fa[N],sz[N],son[N];
void dfs1(int u,int f,int d){
dep[u]=d,fa[u]=f,sz[u]=1;
int gz=G[u].size();
for(int to,i=0;i<gz;i++){
to=G[u][i];
if(to==f)continue;
dfs1(to,u,d+1);
sz[u]+=sz[to];
if(!son[u]||sz[to]>sz[son[u]]) son[u]=to;
}
}
int top[N],tree[N],pre[N],cnt;
void dfs2(int u,int rt){
top[u]=rt,tree[u]=++cnt,pre[tree[u]]=u;
if(!son[u])return ;
dfs2(son[u],rt);
int gz=G[u].size();
for(int i=0,to;i<gz;i++){
to=G[u][i];
if(to==son[u]||to==fa[u]) continue;
dfs2(to,to);
}
}
void init(int n){
cnt = 0;
for(int i=0;i<=n;i++) son[i]=0;
}
void add(int u,int v){
G[u].push_back(v);
G[v].push_back(u);
}
/***
Segmeng begin
*/
int mx[N<<2],sum[N<<2];
# define ll (rt<<1)
# define rr (rt<<1|1)
# define lson (rt<<1),l,mid
# define rson (rt<<1|1),(mid+1),r
# define mid ((l+r)>>1)
void pushup(int rt){
sum[rt]=sum[ll]+sum[rr];
mx[rt]=mmax(mx[ll],mx[rr]);
}
void build(int rt,int l,int r){
if(l==r){
sum[rt]=mx[rt]=w[pre[l]];
return;
}
build(lson);
build(rson);
pushup(rt);
}
void update(int rt,int l,int r,int pos,int val){
if(l==r){
sum[rt]=mx[rt]=val;
return ;
}
if(pos<=mid) update(lson,pos,val);
else update(rson,pos,val);
pushup(rt);
return ;
}
int query_max(int rt,int l,int r,int L,int R){
if(L<=l&&r<=R) return mx[rt];
int ans=-INF;
if(L<=mid) gmax(ans,query_max(lson,L,R));
if(R> mid) gmax(ans,query_max(rson,L,R));
return ans;
}
int query_sum(int rt,int l,int r,int L,int R){
if(L<=l&&r<=R) return sum[rt];
int ans=0;
if(L<=mid) ans+=query_sum(lson,L,R);
if(R> mid) ans+=query_sum(rson,L,R);
return ans;
}
/****
Segment end;
*/
int find_max(int x,int y){
int ans = -INF;
int fx=top[x],fy=top[y];
// printf("%d %d\n",fx,fy);
while(fx!=fy){
if(dep[fx]<dep[fy]) swap(fx,fy),swap(x,y);
gmax(ans,query_max(1,1,n,tree[fx],tree[x]));
x=fa[fx];fx=top[x];
}
if(dep[x]>dep[y]) swap(x,y);
gmax(ans,query_max(1,1,n,tree[x],tree[y]));
return ans;
}
int find_sum(int x,int y){
int ans = 0;
int fx=top[x],fy=top[y];
while(fx!=fy){
if(dep[fx]<dep[fy]) swap(fx,fy),swap(x,y);
ans+=query_sum(1,1,n,tree[fx],tree[x]);
x=fa[fx];fx=top[x];
}
if(dep[x]>dep[y]) swap(x,y);
ans+=query_sum(1,1,n,tree[x],tree[y]);
return ans;
}
void print(){
puts("i : ");for(int i=1;i<=n;i++) printf("%d ",i);puts("");
puts("w[i]: ");for(int i=1;i<=n;i++) printf("%d ",w[i]);puts("");
puts("dep[i]: ");for(int i=1;i<=n;i++) printf("%d ",dep[i]);puts("");
puts("tree[i]: ");for(int i=1;i<=n;i++) printf("%d ",tree[i]);puts("");
puts("tree_w_max[i]: ");for(int i=1;i<=n;i++) printf("%d ",query_max(1,1,n,i,i));puts("");
puts("tree_w_min[i]: ");for(int i=1;i<=n;i++) printf("%d ",query_sum(1,1,n,i,i));puts("");
// for(int i=1;i<=n;i++) printf("%d ",i);
// for(int i=1;i<=n;i++) printf("%d ",i);
// for(int i=1;i<=n;i++) printf("%d ",i);
}
int main(){
scanf("%d",&n);
for(int i=1,u,v;i<n;i++){
scanf("%d%d",&u,&v);
add(u,v);
}
for(int i=1;i<=n;i++) scanf("%d",&w[i]);
init(n);
dfs1(1,0,1),dfs2(1,1);
build(1,1,n);
// print();
// printf("%d\n",query_sum(1,1,n,1,3));
// printf("%d\n",query_sum(1,1,n,4,4));
int q,a,b;
char str[10];
scanf("%d",&q);
while(q--){
scanf("%s %d %d",str,&a,&b);
if(str[0]=='C'){
update(1,1,n,tree[a],b);
w[a]=b;
}
else if(str[1]=='M'){
printf("%d\n",find_max(a,b));
}
else {
printf("%d\n",find_sum(a,b));
}
}
return 0;
}
|
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