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#include <iostream>
#include <cstring>
#include <cstdio>
#include <string>
#include <queue>
#include <set>
#include <map>
using namespace std;
inline int ()
{
int x=0,f=1;char c = getchar();
while(c < '0' || c > '9') {if(c=='-')f=-1;c=getchar();}
while(c >= '0' && c <= '9') x = x*10+c-'0',c=getchar();
return x*f;
}
#define LL long long
#define IN freopen("D:in.txt","r",stdin)
#define OUT freopen("D:out.txt","w",stdout)
const int N = 3e4 + 10, inf = 0x3f3f3f3f;
struct node
{
int to,next;
node(){}
node(int a,int b){to = a; next = b;}
}edge[N << 1];
int num, tot, n; int h[N];
void add(int u,int v){edge[num] = node(v,h[u]);h[u] = num++;}
int dep[N], son[N], fa[N], siz[N], ID[N], top[N], DY[N];
int val[N], Max[N << 2], Sum[N << 2];
void init()
{
num = 0, tot = 0;
for(int i = 0; i < N; i++)
h[i] = son[i] = -1;
}
void dfs1(int u,int f,int d)
{
dep[u] = d; fa[u] = f; siz[u] = 1;
for(int i = h[u]; ~i; i = edge[i].next)
{
int v = edge[i].to;
if(v == f) continue;
dfs1(v, u, d+1);
siz[u] += siz[v];
if(son[u] == -1 || siz[v] > siz[son[u]]) son[u] = v;
}
}
void dfs2(int u,int f,int t)
{
ID[u] = ++tot; top[u] = t;
if(son[u] != -1) dfs2(son[u], u, top[u]);
for(int i = h[u]; ~i; i = edge[i].next)
{
int v = edge[i].to;
if(v == f || v == son[u])continue;
dfs2(v, u, v);
}
}
void build(int id, int l, int r)
{
if(l == r){Max[id] = Sum[id] = val[l]; return;}
int mid = l+r>>1;
build(id << 1, l, mid);
build(id << 1|1, mid+1, r);
Max[id] = max(Max[id<<1], Max[id<<1|1]);
Sum[id] = Sum[id<<1] + Sum[id<<1|1];
}
void updata(int id, int l, int r, int qid, int w)
{
if(l == r && r == qid) {Max[id] = Sum[id] = w; return;}
int mid = l+r >> 1;
if(qid <= mid) updata(id << 1, l, mid, qid, w);
else updata(id << 1|1, mid+1, r, qid, w);
Max[id] = max(Max[id<<1], Max[id<<1|1]);
Sum[id] = Sum[id<<1] + Sum[id<<1|1];
}
int query1(int id, int l, int r, int ql, int qr)
{
int res = 0;
if(l > qr || r < ql) return 0;
if(l >= ql && r <= qr) return Sum[id];
int mid = l+r>>1;
if(ql <= mid) res += query1(id << 1, l, mid, ql, qr);
if(qr > mid) res += query1(id << 1|1, mid+1, r, ql, qr);
return res;
}
int query2(int id, int l, int r, int ql, int qr)
{
int res = -inf;
if(l > qr || r < ql) return -inf;
if(l >= ql && r <= qr) return Max[id];
int mid = l+r>>1;
if(ql <= mid) res = query2(id << 1, l, mid, ql, qr);
if(qr > mid) res = max(res, query2(id << 1|1, mid+1, r, ql, qr));
return res;
}
void Work_pre()
{
dfs1(1, 1, 0);
dfs2(1, 1, 1);
}
int workS(int a,int b)
{
int f1 = top[a], f2 = top[b], res = 0;
while(f1 != f2)
{
if(dep[f1] > dep[f2]) swap(a,b),swap(f1,f2);
res += query1(1, 1, n, ID[top[b]], ID[b]);
b = fa[f2], f2 = top[b];
}
if(dep[a] > dep[b]) swap(a,b);
int th = query1(1, 1, n, ID[a], ID[b]);
res += th;
return res;
}
int workM(int a, int b)
{
int f1 = top[a], f2 = top[b], res = -inf;
while(f1 != f2)
{
if(dep[f1] > dep[f2]) swap(a,b),swap(f1,f2);
res = max(res, query2(1, 1, n, ID[top[b]], ID[b]));
b = fa[f2], f2 = top[b];
}
if(dep[a] > dep[b]) swap(a,b);
res = max(res, query2(1, 1, n, ID[a], ID[b]));
return res;
}
int main()
{
int u,v,x;
while(~scanf("%d",&n))
{
init();
for(int i = 0; i < n-1; i++)
u=read(),v=read(), add(u,v), add(v,u);
Work_pre();
for(int i = 1; i <= n; i++) scanf("%d", &x),val[ID[i]] = x;
build(1, 1, tot);
int q;
scanf("%d",&q);
for(int i = 0; i < q; i++)
{
char str[15]; int a,b;
scanf("%s", str);
a=read(), b=read();
if(str[0] == 'C') updata(1, 1, n, ID[a], b);
else if(str[1] == 'S') printf("%dn",workS(a,b));
else printf("%dn",workM(a,b));
}
}
return 0;
}
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