树链剖分 HYSBZ - 1036

#include<iostream>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<cstdlib>
#include<climits>
#include<stack>
#include<vector>
#include<queue>
#include<set>
#include<map>
//#include<regex>
#include<cstdio>
#define up(i,a,b)  for(int i=a;i<b;i++)
#define dw(i,a,b)  for(int i=a;i>b;i--)
#define upd(i,a,b) for(int i=a;i<=b;i++)
#define dwd(i,a,b) for(int i=a;i>=b;i--)
//#define local
typedef long long ll;
const double esp = 1e-6;
const double pi = acos(-1.0);
const int INF = 0x3f3f3f3f;
const int inf = 1e9;
using namespace std;
ll read()
{
	char ch = getchar(); ll x = 0, f = 1;
	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;
}
typedef pair<int, int> pir;
#define lson l,mid,root<<1
#define rson mid+1,r,root<<1|1
#define lrt root<<1
#define rrt root<<1|1
const int N = 3e4 + 10;
int dep[N], id[N], son[N], fa[N], top[N], siz[N], rk[N], wi[N];
struct node { int to, next; }edge[2*N];
int head[N];
int cnt = 0;
int num = 0;
int n, q;
ll maxn[N << 2];
ll sum[N << 2];
void pushup(int root)
{
	maxn[root] = max(maxn[lrt], maxn[rrt]);
	sum[root] = sum[lrt] + sum[rrt];
}
void build(int l, int r, int root)
{
	if (l == r)
	{
		sum[root]= maxn[root] = wi[rk[l]];
		return;
	}
	int mid = (l + r) >> 1;
	build(lson); build(rson);
	pushup(root);
}
void update(int l,int r,int root,int lf,int rt,int val)
{
	if (lf <= l && r <= rt)
	{
		maxn[root] = val;
		sum[root] = (r - l + 1)*1ll*val;
		return;
	}
	int mid = (l + r) >> 1;
	if(lf<=mid)update(lson, lf, rt, val);
	if (rt > mid)update(rson, lf, rt, val);
	pushup(root);
}
ll querrysum(int l, int r, int root, int lf, int rt)
{
	if (lf <= l && r <= rt)
	{
		return sum[root];
	}
	int mid = (l + r) >> 1;
	ll ans = 0;
	if (lf <= mid)ans += querrysum(lson, lf, rt);
	if (rt > mid)ans += querrysum(rson, lf, rt);
	return ans;
}
ll querrymax(int l, int r, int root, int lf, int rt)
{
	if (lf <= l && r <= rt)
	{
		return maxn[root];
	}
	int mid = (l + r) >> 1;
	ll ans = -1e18;
	if (lf <= mid)ans = max(ans, querrymax(lson, lf, rt));
	if (rt > mid)ans = max(ans, querrymax(rson, lf, rt));
	return ans;
}
void addedge(int u, int v)
{
	edge[cnt].to = v;
	edge[cnt].next = head[u];
	head[u] = cnt++;
}
void dfs1(int u,int pre,int d)
{
	dep[u] = d;
	siz[u] = 1;
	fa[u] = pre;
	for (int i = head[u]; ~i; i = edge[i].next)
	{
		int t = edge[i].to;
		if (t == pre)continue;
		dfs1(t, u, d + 1);
		siz[u] += siz[t];
		if (son[u] == -1 || siz[t] > siz[son[u]])
			son[u] = t;
	}
}
void dfs2(int u, int tp)
{
	top[u] = tp;
	id[u] = ++num;
	rk[num] = u;
	if (son[u] == -1)return;
	dfs2(son[u], tp);
	for (int i = head[u]; ~i; i = edge[i].next)
	{
		int v = edge[i].to;
		if (v == fa[u] || v == son[u])continue;
		dfs2(v, v);
	}
}
void rgupdate(int x, int y,int val)
{
	while (top[x] != top[y])
	{
		if (dep[top[x]] < dep[top[y]])swap(x, y);
		update(1, n, 1, id[top[x]], id[x], val);
		x = fa[top[x]];
	}
	if (dep[x] < dep[y])swap(x, y);
	update(1, n, 1, id[y], id[x], val);
}
ll rgsum(int x, int y)
{
	ll ans = 0;
	while (top[x] != top[y])
	{
		if (dep[top[x]] < dep[top[y]])swap(x, y);
		ans += querrysum(1, n, 1, id[top[x]], id[x]);
		x = fa[top[x]];
	}
	if (dep[x] < dep[y])swap(x, y);
	ans += querrysum(1, n, 1, id[y], id[x]);
	return ans;
}
ll rgmax(int x, int y)
{
	ll ans = -1e18;
	while (top[x] != top[y])
	{
		if (dep[top[x]] < dep[top[y]])swap(x, y);
		ans = max(ans, querrymax(1, n, 1, id[top[x]], id[x]));
		x = fa[top[x]];
	}
	if (dep[x] < dep[y])swap(x, y);
	ans = max(ans, querrymax(1, n, 1, id[y], id[x]));
	return ans;
}
int main()
{
	n = read();
	memset(head, -1, sizeof(head));
	memset(son, -1, sizeof(son));
	int u, v, w;
	up(i, 0, n - 1)
	{
		u = read(), v = read();
		addedge(u, v); addedge(v, u);
	}
	upd(i, 1, n)wi[i] = read();
	dfs1(1, -1, 1);
	dfs2(1, 1);
	build(1, n, 1);
	q = read();
	char s[10];
	while (q--)
	{
		scanf("%s", s);
		if (s[0] == 'C')
		{
			u = read(), w = read();
			rgupdate(u, u, w);
		}
		else if (s[1] == 'M')
		{
			u = read(), v = read();
			printf("%lld\n", rgmax(u, v));
		}
		else {
			u = read(), v = read();
			printf("%lld\n", rgsum(u, v));
		}
	}
	return 0;
}