#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<queue>
#include<cmath>
#define inc(i,l,r) for(int i=l;i<=r;i++)
#define dec(i,l,r) for(int i=l;i>=r;i--)
#define link(x) for(edge *j=h[x];j;j=j->next)
#define inf 1000000007
#define eps 1e-8
#define mem(a) memset(a,0,sizeof(a))
#define ll long long
#define succ(x) (1<<x)
#define lowbit(x) (x&(-x))
#define sqr(x) ((x)*(x))
#define ls T[i<<1]
#define rs T[i<<1|1]
#define op T[i]
#define NM 30005
#define nm 60005
#define pi 3.141592653
using namespace std;
int read(){
int x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
return f*x;
}
struct edge{int t;edge*next;}e[nm],*h[NM],*o=e;
void add(int x,int y){o->t=y;o->next=h[x];h[x]=o++;}
int top[NM],TOP,size[NM],son[NM],d[NM],f[NM],tot,id[NM];
int n,m,_x,_y,a[NM];
char _s[10];
void dfs1(int x){
link(x)if(!f[j->t]){
f[j->t]=x;d[j->t]=d[x]+1;
dfs1(j->t);
if(size[j->t]>size[son[x]])son[x]=j->t;
size[x]+=size[j->t];
}
size[x]++;
}
void dfs2(int x){
top[x]=TOP;id[x]=++tot;
if(son[x])dfs2(son[x]);
link(x)if(!top[j->t])dfs2(TOP=j->t);
}
struct info{
ll s;int m,size;
info operator+(const info&o){
info f;f.s=s+o.s;
f.size=size+o.size;
f.m=max(m,o.m);
return f;
}
}T[4*NM];
void build(int i,int x,int y){
int t=x+y>>1;
if(x==y){op.s=op.m=a[x];op.size=1;return;}
build(i<<1,x,t);build(i<<1|1,t+1,y);
op=rs+ls;
}
void mod(int i,int x,int y){
int t=x+y>>1;
if(x==y){op.s=op.m=_y;return;}
if(_x<=t)mod(i<<1,x,t);else mod(i<<1|1,t+1,y);
op=ls+rs;
}
ll sum(int i,int x,int y){
int t=x+y>>1;
if(_y<x||y<_x)return 0;
if(_x<=x&&y<=_y)return op.s;
return sum(i<<1,x,t)+sum(i<<1|1,t+1,y);
}
int query(int i,int x,int y){
int t=x+y>>1;
if(_y<x||y<_x)return -inf;
if(_x<=x&&y<=_y)return op.m;
return max(query(i<<1,x,t),query(i<<1|1,t+1,y));
}
int _query1(int x,int y){
int s=-inf;
for(;top[x]!=top[y];x=f[top[x]]){
if(d[top[x]]<d[top[y]])swap(x,y);
_x=id[top[x]];_y=id[x];s=max(s,query(1,1,n));
}
if(d[x]>d[y])swap(x,y);
_x=id[x];_y=id[y];s=max(s,query(1,1,n));
return s;
}
ll _query2(int x,int y){
ll s=0;
for(;top[x]!=top[y];x=f[top[x]]){
if(d[top[x]]<d[top[y]])swap(x,y);
_x=id[top[x]];_y=id[x];s+=sum(1,1,n);
}
if(d[x]>d[y])swap(x,y);
_x=id[x];_y=id[y];s+=sum(1,1,n);
return s;
}
int main(){
freopen("data.in","r",stdin);
n=read();
inc(i,1,n-1){_x=read();_y=read();add(_x,_y);add(_y,_x);}
dfs1(f[1]=1);dfs2(TOP=1);
inc(i,1,n)a[id[i]]=read();
build(1,1,n);
m=read();
while(m--){
scanf("%s",_s);
_x=read();_y=read();
if(_s[0]=='C'){
_x=id[_x];mod(1,1,n);
}else if(_s[1]=='M')printf("%d\n",_query1(_x,_y));
else printf("%lld\n",_query2(_x,_y));
}
return 0;
}
