#include <bits/stdc++.h>
using namespace std;
const int N = 100005;
const int inf = 1e9;
inline int read()
{
int x = 0, f = 1; char ch = getchar();
while (ch < '0' || ch > '9') {if (ch == '-') f = -1; ch = getchar();}
while (ch >= '0' && ch <= '9') {x = x * 10 + ch - '0'; ch = getchar();}
return x * f;
}
int n, Q, w[N];
vector<int> to[N];
int fa[N], deep[N], sz[N], son[N];
void dfs1(int x)
{
sz[x] = 1;
for(int i = 0; i < to[x].size(); i++)
{
int k = to[x][i];
if(k == fa[x]) continue;
fa[k] = x; deep[k] = deep[x] + 1;
dfs1(k); sz[x] += sz[k];
if(sz[k] > sz[son[x]]) son[x] = k;
}
}
int tot, id[N], dfn[N], top[N];
void dfs2(int x, int tp)
{
dfn[x] = ++tot; id[tot] = x; top[x] = tp;
if(son[x]) dfs2(son[x], tp);
for(int i = 0; i < to[x].size(); i++)
{
int k = to[x][i];
if(k != fa[x] && k != son[x]) dfs2(k, k);
}
}
struct node
{
int l, r, sum, mx;
}T[N << 3];
void pushup(int p)
{
T[p].sum = T[p << 1].sum + T[p << 1 | 1].sum;
T[p].mx = max(T[p << 1].mx, T[p << 1 | 1].mx);
}
void build(int p, int x, int y)
{
T[p].l = x; T[p].r = y;
if(x == y) {T[p].sum = T[p].mx = w[id[x]]; return;}
int mid = (x + y) >> 1;
build(p << 1, x, mid); build(p << 1 | 1, mid + 1, y);
pushup(p);
}
void change(int p, int x, int v)
{
int pl = T[p].l, pr = T[p].r;
if(pl == x && pr == x)
{
T[p].sum = T[p].mx = v;
return;
}
int mid = (pl + pr) >> 1;
if(x <= mid) change(p << 1, x, v);
else change(p << 1 | 1, x, v);
pushup(p);
}
int query_max(int p, int x, int y)
{
int pl = T[p].l, pr = T[p].r;
if(pl == x && pr == y) return T[p].mx;
int mid = (pl + pr) >> 1;
if(y <= mid) return query_max(p << 1, x, y);
else if(x > mid) return query_max(p << 1 | 1, x, y);
else return max(query_max(p << 1, x, mid), query_max(p << 1 | 1, mid + 1, y));
}
int query_sum(int p, int x, int y)
{
int pl = T[p].l, pr = T[p].r;
if(pl == x && pr == y) return T[p].sum;
int mid = (pl + pr) >> 1;
if(y <= mid) return query_sum(p << 1, x, y);
else if(x > mid) return query_sum(p << 1 | 1, x, y);
return query_sum(p << 1, x, mid) + query_sum(p << 1 | 1, mid + 1, y);
}
int QMAX(int x, int y)
{
int cnt = -inf;
while(top[x] != top[y])
{
if(deep[top[x]] < deep[top[y]]) swap(x, y);
cnt = max(cnt, query_max(1, dfn[top[x]], dfn[x]));
x = fa[top[x]];
}
if(deep[x] < deep[y]) swap(x, y);
cnt = max(cnt, query_max(1, dfn[y], dfn[x]));
return cnt;
}
int QSUM(int x, int y)
{
int cnt = 0;
while(top[x] != top[y])
{
if(deep[top[x]] < deep[top[y]]) swap(x, y);
cnt += query_sum(1, dfn[top[x]], dfn[x]);
x = fa[top[x]];
}
if(deep[x] < deep[y]) swap(x, y);
cnt += query_sum(1, dfn[y], dfn[x]);
return cnt;
}
int main()
{
n = read();
for(int i = 1; i < n; i++)
{
int x = read(), y = read();
to[x].push_back(y); to[y].push_back(x);
}
for(int i = 1; i <= n; i++) w[i] = read();
dfs1(1);
dfs2(1, 0);
build(1, 1, n);
Q = read();
while(Q--)
{
char op[10]; scanf("%s", op);
int x = read(), y = read();
if(op[0] == 'C') change(1, dfn[x], y);
else if(op[1] == 'M') printf("%d\n", QMAX(x, y));
else printf("%d\n", QSUM(x, y));
}
return 0;
}
