注意负权值

#include<bits/stdc++.h>
using namespace std;

typedef long long LL;
const int N = 3e4 + 10;
const LL inf = 1e9;

LL num[N];
vector<int> G[N];
int fa[N], siz[N], dep[N], son[N];

void fir_dfs(int x, int x_fa) {
	fa[x] = x_fa;
	siz[x] = 1;
	son[x] = -1;
	dep[x] = dep[x_fa] + 1;
	for (int y : G[x]) if (y != x_fa) {
		fir_dfs(y, x);
		if ( (son[x] == -1) || (siz[son[x]] < siz[y]) ) {
			son[x] = y;
		}
		siz[x] += siz[y];
	}
}

int tsp, dfn[N], r_dfn[N], top[N];

void sec_dfs(int x, int tp) {
	tsp ++;
	dfn[x] = tsp;
	r_dfn[dfn[x]] = x;
	top[x] = tp;
	
	if (son[x] != -1) {
		sec_dfs(son[x], tp);
	}
	for (int y : G[x]) if (son[x] != y && y != fa[x]) {
		sec_dfs(y, y);
	}
}

#define lc(p) p << 1
#define rc(p) (p << 1) | 1

struct node {
	int l, r;
	LL mx, sum;
} tr[4 * N];

void pushup(int p) {
	tr[p].sum = tr[lc(p)].sum + tr[rc(p)].sum;
	tr[p].mx = max(tr[lc(p)].mx, tr[rc(p)].mx);
}

void build(int p, int l, int r) {
	tr[p] = {l, r, -inf, -inf};
	if (l == r) {
		tr[p] = {l, r, num[r_dfn[l]], num[r_dfn[l]]};
		return ;
	}
	
	int mid = (l + r) >> 1;
	build(lc(p), l, mid);
	build(rc(p), mid + 1, r);
	pushup(p);
}

void change(int p, int x, LL c) {
	if (tr[p].l > x || tr[p].r < x) {
		return ;
	}
	if (tr[p].l == tr[p].r) {
		tr[p].mx = tr[p].sum = c;
		return ;
	}
	
	change(lc(p), x, c);
	change(rc(p), x, c);
	pushup(p);
}

LL find_max(int p, int l, int r) {
	if (tr[p].l > r || tr[p].r < l) {
		return -inf;
	}
	if (l <= tr[p].l && tr[p].r <= r) {
		return tr[p].mx;
	}
	
	return max(find_max(lc(p), l, r), find_max(rc(p), l, r));
}

LL get_sum(int p, int l, int r) {
	if (tr[p].l > r || tr[p].r < l) {
		return 0;
	}
	if (l <= tr[p].l && tr[p].r <= r) {
		return tr[p].sum;
	}
	
	return get_sum(lc(p), l, r) + get_sum(rc(p), l, r);
}

LL query_max(int x, int y) {
	LL res = -inf;
	while (top[x] != top[y]) {
		if (dep[top[x]] < dep[top[y]]) {
			swap(x, y);
		}
		res = max(res, find_max(1, dfn[top[x]], dfn[x]));
		x = fa[top[x]];
	}
	
	if (dep[x] > dep[y]) {
		swap(x, y);
	}
	res = max(res, find_max(1, dfn[x], dfn[y]));
	return res;
}

LL query_sum(int x, int y) {
	LL res = 0;
	while (top[x] != top[y]) {
		if (dep[top[x]] < dep[top[y]]) {
			swap(x, y);
		}
		res += get_sum(1, dfn[top[x]], dfn[x]);
		x = fa[top[x]];
	}
	
	if (dep[x] > dep[y]) {
		swap(x, y);
	}
	res += get_sum(1, dfn[x], dfn[y]);
	return res;
}

int main () {
	ios::sync_with_stdio(false);
	cin.tie(0);
	
	int n;
	cin >> n;
	for (int i = 1; i < n; i ++) {
		int x, y;
		cin >> x >> y;
		G[x].push_back(y);
		G[y].push_back(x);
	}
	
	for (int i = 1; i <= n; i ++) {
		cin >> num[i];
	}
	
	dep[0] = 0;
	fir_dfs(1, 0);
	tsp = 0;
	sec_dfs(1, 1);
	
	build(1, 1, n);
	
	int q;
	cin >> q;
	for (int i = 1; i <= q; i ++) {
		char s[10];
		cin >> s;
		if(s[0] == 'C') {
			int x; LL c;
			cin >> x >> c;
			change(1, dfn[x], c);
		}
		else if (s[0] == 'Q' && s[1] == 'M') {
			int x, y;
			cin >> x >> y;
			cout << query_max(x, y) << "\n";
		}
		else {
			int x, y;
			cin >> x >> y;
			cout << query_sum(x, y) << "\n";
		}
	}
	
	return 0;
}