/*
 * Author:  sweat123
 * Created Time:  2016/7/13 14:46:25
 * File Name: main.cpp
 */
#include<set>
#include<map>
#include<queue>
#include<stack>
#include<cmath>
#include<string>
#include<vector>
#include<cstdio>
#include<time.h>
#include<cstring>
#include<iostream>
#include<algorithm>
#define INF 1<<30
#define MOD 1000000007
#define ll long long
#define lson l,m,rt<<1
#define key_value ch[ch[root][1]][0]
#define rson m+1,r,rt<<1|1
#define pi acos(-1.0)
using namespace std;
const int MAXN = 80010;
struct node{
    int to;
    int next;
}edge[MAXN*2];
int dp[MAXN*2][20],ind,pre[MAXN],a[MAXN],first[MAXN],rev[MAXN*2],tot,dfn[MAXN*2],vis[MAXN],fa[MAXN],n,m;
void add(int x,int y){
    edge[ind].to = y;
    edge[ind].next = pre[x];
    pre[x] = ind ++;
}
bool cmp(int x,int y){
    return x > y;
}
void dfs(int rt,int deq,int pa){
    vis[rt] = 1;
    rev[++tot] = rt;
    fa[rt] = pa;
    dfn[tot] = deq;
    first[rt] = tot;
    for(int i = pre[rt]; i != -1; i = edge[i].next){
        int t = edge[i].to;
        if(!vis[t]){
            dfs(t,deq+1,rt);
            rev[++tot] = rt;
            dfn[tot] = deq;
        }
    }
}
int b[MAXN],cnt;
void rmq(){
    for(int i = 1; i <= tot; i++){
        dp[i][0] = i;
    }
    for(int i = 1; i < 20; i++){
        for(int j = 1; j + (1 << i) - 1 <= tot; j++){
            int x = dp[j][i-1];
            int y = dp[j+(1<<(i-1))][i-1];
            if(dfn[x] > dfn[y]){
                dp[j][i] = y;
            } else{
                dp[j][i] = x;
            }
        }
    }
}
int lca(int x,int y){
    x = first[x];
    y = first[y];
    if(x > y)swap(x,y);
    int k = (int)(log(y - x + 1) * 1.0 / log(2.0));
    int l = dp[x][k];
    int r = dp[y - (1<<k) + 1][k];
    if(dfn[l] > dfn[r]){
        return r;
    } else {
        return l;
    }
}
int main(){
    while(~scanf("%d%d",&n,&m)){
        for(int i = 1; i <= n; i++)scanf("%d",&a[i]);
        ind = 0;
        memset(pre,-1,sizeof(pre));
        for(int i = 1; i < n; i++){
            int x,y;
            scanf("%d%d",&x,&y);
            add(x,y),add(y,x);
        }
        tot = 0;
        memset(vis,0,sizeof(vis));
        dfs(1,1,-1);
        rmq();
        while(m --){
            int k,x,y;
            scanf("%d%d%d",&k,&x,&y);
            if(k == 0){
                a[x] = y;
            } else{
                if(y > n){
                    printf("invalid request!\n");
                    continue;
                }
                cnt = 0;
                int tp = rev[lca(x,y)];
                b[cnt++] = a[tp];
                while(x != tp){
                    b[cnt++] = a[x];
                    x = fa[x];
                }
                while(y != tp){
                    b[cnt++] = a[y];
                    y = fa[y];
                }
                sort(b,b+cnt,cmp);
                if(k > cnt) printf("invalid request!\n");
                else printf("%d\n",b[k-1]);
            }
        }
    }
    return 0;
}