1 /*************************************************************************
  2     > File Name: 3966.cpp
  3     > Author: Nature
  4     > Mail: 564374850@qq.com
  5     > Created Time: Sun 05 Oct 2014 01:20:20 PM CST
  6 ************************************************************************/
  7 #pragma comment(linker,"/STACK:1024000000,1024000000")
  8 #include <cstdio>
  9 #include <cstring>
 10 #include <cstdlib>
 11 #include <iostream>
 12 #include <algorithm>
 13 using namespace std;
 14 #define lp (p << 1)
 15 #define rp (p << 1|1)
 16 #define getmid(l,r) (l + (r - l) / 2)
 17 const int maxn = 50010;
 18
 19 int N,M,P;
 20 int A[maxn];
 21 int first[maxn],next[maxn << 1],ver[maxn << 1],ecnt;
 22 int dep[maxn],sz[maxn],son[maxn],fa[maxn],top[maxn],w[maxn],aw[maxn],tsz;
 23
 24 struct node{
 25     int add;
 26     int val;
 27 }t[maxn << 2];
 28
 29 void Add_edge(int u,int v){
 30     next[++ecnt] = first[u];
 31     ver[ecnt] = v;
 32     first[u] = ecnt;
 33 }
 34
 35 void Dfs(int p,int pre,int d){
 36     sz[p] = 1;
 37     dep[p] = d;
 38     fa[p] = pre;
 39     son[p] = -1;
 40     int v,tmp = 0;
 41     for(int i = first[p]; i != -1; i = next[i]) if((v = ver[i]) != pre){
 42         Dfs(v,p,d + 1);
 43         if(sz[v] > tmp){
 44             son[p] = v;
 45             tmp = sz[v];
 46         }
 47         sz[p] += sz[v];
 48     }
 49 }
 50
 51 void Dfs_pos(int p,int tp){
 52     w[p] = ++tsz;
 53     aw[tsz] = p;
 54     top[p] = tp;
 55     if(son[p] != -1) Dfs_pos(son[p],tp);
 56     for(int i = first[p]; i != -1; i = next[i]){
 57         int v = ver[i];
 58         if(v != son[p] && v != fa[p])
 59             Dfs_pos(v,v);
 60     }
 61 }
 62
 63 void Build_tree(int p,int l,int r){
 64     t[p].add = 0;
 65     if(l == r){
 66         t[p].val = A[aw[l]];
 67         return;
 68     }
 69     int mid = getmid(l,r);
 70     Build_tree(lp,l,mid);
 71     Build_tree(rp,mid + 1,r);
 72 }
 73
 74 void Update_tree(int a,int b,int c,int p,int l,int r){
 75     if(a <= l && r <= b){
 76         t[p].add += c;
 77         return;
 78     }
 79     int mid = getmid(l,r);
 80     if(a <= mid) Update_tree(a,b,c,lp,l,mid);
 81     if(b > mid) Update_tree(a,b,c,rp,mid + 1,r);
 82 }
 83
 84 int Query_tree(int a,int p,int l,int r,int plu){
 85     if(l == r)
 86         return t[p].val + t[p].add + plu;
 87     int mid = getmid(l,r);
 88     if(a <= mid) return Query_tree(a,lp,l,mid,plu + t[p].add);
 89     else return Query_tree(a,rp,mid + 1,r,plu + t[p].add);
 90 }
 91
 92 void Change(int a,int b,int c){
 93     int f1 = top[a],f2 = top[b];
 94     while(f1 != f2){
 95         if(dep[f1] > dep[f2]){
 96             swap(a,b);
 97             swap(f1,f2);
 98         }
 99         Update_tree(w[f2],w[b],c,1,1,tsz);
100         b = fa[f2];
101         f2 = top[b];
102     }
103     if(dep[a] > dep[b]) swap(a,b);
104     Update_tree(w[a],w[b],c,1,1,tsz);
105 }
106
107 void Init(){
108     memset(first,-1,sizeof(first));
109     ecnt = 0;
110     tsz = 0;
111 }
112
113 int main(){
114     char s[5];
115     int a,b,c;
116     while(scanf("%d%d%d",&N,&M,&P) != EOF){
117         Init();
118         for(int i = 1; i <= N; ++i)
119             scanf("%d",A + i);
120         for(int i = 1; i < N; ++i){
121             scanf("%d%d",&a,&b);
122             Add_edge(a,b);
123             Add_edge(b,a);
124         }
125         Dfs(1,0,0);
126         Dfs_pos(1,1);
127         Build_tree(1,1,tsz);
128         for(int i = 1; i <= P; ++i){
129             scanf("%s%d",s,&a);
130             if(s[0] == 'I' || s[0] == 'D'){
131                 scanf("%d%d",&b,&c);
132                 if(s[0] == 'D') Change(a,b,-c);
133                 else Change(a,b,c);
134             }
135             else printf("%d\n",Query_tree(w[a],1,1,tsz,0));
136         }
137     }
138     return 0;
139 }