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

typedef long long int LL;

const int    INF = (~(1<<31));
const int    N   = 30000+7;
const double eps = 1e-7;

inline int read(){
    int x=0,f=1;char ch = getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while('0'<=ch&&ch<='9'){x=(x<<3)+(x<<1)+ch-'0';ch=getchar();}
    return x*f;
}
inline int gmax(int &x,int y){if(y>x)x=y;}
inline int gmin(int &x,int y){if(y<x)x=y;}
inline int mmax(int  x,int y){if(y>x)x=y;return x; }
inline int mmin(int  x,int y){if(y<x)x=y;return x; }
/****************************************************/

int w[N],n;
vector<int >G[N];

/***
tree cut
*/
int dep[N],fa[N],sz[N],son[N];

void dfs1(int u,int f,int d){
    dep[u]=d,fa[u]=f,sz[u]=1;
    int gz=G[u].size();
    for(int to,i=0;i<gz;i++){
        to=G[u][i];
        if(to==f)continue;
        dfs1(to,u,d+1);
        sz[u]+=sz[to];
        if(!son[u]||sz[to]>sz[son[u]]) son[u]=to;
    }
}

int top[N],tree[N],pre[N],cnt;

void dfs2(int u,int rt){
    top[u]=rt,tree[u]=++cnt,pre[tree[u]]=u;
    if(!son[u])return ;
    dfs2(son[u],rt);
    int gz=G[u].size();
    for(int i=0,to;i<gz;i++){
        to=G[u][i];
        if(to==son[u]||to==fa[u]) continue;
        dfs2(to,to);
    }
}

void init(int n){
    cnt = 0;
    for(int i=0;i<=n;i++) son[i]=0;
}

void add(int u,int v){
    G[u].push_back(v);
    G[v].push_back(u);
}

/***
Segmeng begin
*/
int mx[N<<2],sum[N<<2];

# define ll   (rt<<1)
# define rr   (rt<<1|1)
# define lson (rt<<1),l,mid
# define rson (rt<<1|1),(mid+1),r
# define mid  ((l+r)>>1)

void pushup(int rt){
    sum[rt]=sum[ll]+sum[rr];
    mx[rt]=mmax(mx[ll],mx[rr]);
}

void build(int rt,int l,int r){
    if(l==r){
        sum[rt]=mx[rt]=w[pre[l]];
        return;
    }
    build(lson);
    build(rson);
    pushup(rt);
}

void update(int rt,int l,int r,int pos,int val){
    if(l==r){
        sum[rt]=mx[rt]=val;
        return ;
    }
    if(pos<=mid) update(lson,pos,val);
    else         update(rson,pos,val);
    pushup(rt);
    return ;
}

int query_max(int rt,int l,int r,int L,int R){
    if(L<=l&&r<=R)   return mx[rt];
    int ans=-INF;
    if(L<=mid) gmax(ans,query_max(lson,L,R));
    if(R> mid) gmax(ans,query_max(rson,L,R));
    return ans;
}

int query_sum(int rt,int l,int r,int L,int R){
    if(L<=l&&r<=R)   return sum[rt];
    int ans=0;
    if(L<=mid) ans+=query_sum(lson,L,R);
    if(R> mid) ans+=query_sum(rson,L,R);
    return ans;
}
/****
Segment end;
*/
int find_max(int x,int y){
    int ans = -INF;
    int fx=top[x],fy=top[y];
//    printf("%d %d\n",fx,fy);
    while(fx!=fy){
        if(dep[fx]<dep[fy]) swap(fx,fy),swap(x,y);
        gmax(ans,query_max(1,1,n,tree[fx],tree[x]));
        x=fa[fx];fx=top[x];
    }
    if(dep[x]>dep[y]) swap(x,y);
    gmax(ans,query_max(1,1,n,tree[x],tree[y]));
    return ans;
}

int find_sum(int x,int y){
    int ans = 0;
    int fx=top[x],fy=top[y];
    while(fx!=fy){
        if(dep[fx]<dep[fy]) swap(fx,fy),swap(x,y);
        ans+=query_sum(1,1,n,tree[fx],tree[x]);
        x=fa[fx];fx=top[x];
    }
    if(dep[x]>dep[y]) swap(x,y);
    ans+=query_sum(1,1,n,tree[x],tree[y]);
    return ans;
}

void print(){
    puts("i : ");for(int i=1;i<=n;i++) printf("%d ",i);puts("");
    puts("w[i]: ");for(int i=1;i<=n;i++) printf("%d ",w[i]);puts("");
    puts("dep[i]: ");for(int i=1;i<=n;i++) printf("%d ",dep[i]);puts("");
    puts("tree[i]: ");for(int i=1;i<=n;i++) printf("%d ",tree[i]);puts("");
    puts("tree_w_max[i]: ");for(int i=1;i<=n;i++) printf("%d ",query_max(1,1,n,i,i));puts("");
    puts("tree_w_min[i]: ");for(int i=1;i<=n;i++) printf("%d ",query_sum(1,1,n,i,i));puts("");
//    for(int i=1;i<=n;i++) printf("%d ",i);
//    for(int i=1;i<=n;i++) printf("%d ",i);
//    for(int i=1;i<=n;i++) printf("%d ",i);

}

int main(){
    scanf("%d",&n);
    for(int i=1,u,v;i<n;i++){
        scanf("%d%d",&u,&v);
        add(u,v);
    }
    for(int i=1;i<=n;i++)    scanf("%d",&w[i]);

    init(n);
    dfs1(1,0,1),dfs2(1,1);
    build(1,1,n);

//    print();

//    printf("%d\n",query_sum(1,1,n,1,3));
//    printf("%d\n",query_sum(1,1,n,4,4));

    int q,a,b;
    char str[10];
    scanf("%d",&q);
    while(q--){
        scanf("%s %d %d",str,&a,&b);
        if(str[0]=='C'){
            update(1,1,n,tree[a],b);
            w[a]=b;
        }
        else if(str[1]=='M'){
            printf("%d\n",find_max(a,b));
        }
        else {
            printf("%d\n",find_sum(a,b));
        }
    }
    return 0;
}