#include <bits/stdc++.h>
#define Nmax 100005
#define INF 1000000000
#define pb push_back

using namespace std;

int val[Nmax],lvl[Nmax],Father[Nmax],Wh[Nmax],nr;
int poz[Nmax],cnt[Nmax],n;
vector <int> L[Nmax],Lant[Nmax];

class Aint
{
public:
    vector <int> aint;
    inline void upd(int nod, int st, int dr, int p, int x)
    {
        if(st==dr)
        {
            aint[nod]=x; return;
        }
        int mij=((st+dr)>>1);
        if(p<=mij) upd(2*nod,st,mij,p,x);
        else upd(2*nod+1,mij+1,dr,p,x);
        aint[nod]=max(aint[2*nod],aint[2*nod+1]);
    }
    inline int qry(int nod, int st, int dr, int x, int y)
    {
        if(st==x && y==dr) return aint[nod];
        int mij=((st+dr)>>1);
        if(y<=mij) return qry(2*nod,st,mij,x,y);
        if(x>mij) return qry(2*nod+1,mij+1,dr,x,y);
        return max(qry(2*nod,st,mij,x,mij),qry(2*nod+1,mij+1,dr,mij+1,y));
    }
} v[Nmax];

inline void Dfs(int nod, int tata)
{
    int node=0;
    cnt[nod]=1;
    for(auto it : L[nod])
    {
        if(it==tata) continue;
        lvl[it]=lvl[nod]+1;
        Dfs(it,nod);
        if(cnt[it]>cnt[node]) node=it;
        cnt[nod]+=cnt[it];
    }
    if(!node)
    {
        Wh[nod]=++nr; poz[nod]=1;
        Lant[nr].pb(nod);
    }
    else
    {
        Wh[nod]=Wh[node]; poz[nod]=poz[node]+1;
        Lant[Wh[nod]].pb(nod);
    }
    for(auto it : L[nod])
    {
        if(it==tata || it==node) continue;
        Father[Wh[it]]=nod;
    }
}

inline void Make_HPD()
{
    for(int i=1;i<=nr;++i)
    {
        v[i].aint.resize(4*Lant[i].size()+2);
        for(int j=0;j<Lant[i].size();++j) v[i].upd(1,1,Lant[i].size(),j+1,val[Lant[i][j]]);
    }
}

int main()
{
    int m,x,y,t,ans,i;
    ifstream cin("heavypath.in");
    ofstream cout("heavypath.out");
    cin>>n>>m;
    for(i=1;i<=n;++i) cin>>val[i];
    for(i=1;i<n;++i)
    {
        cin>>x>>y;
        L[x].pb(y); L[y].pb(x);
    }
    lvl[1]=1; Dfs(1,0);
    Make_HPD();
    while(m--)
    {
        cin>>t>>x>>y;
        if(!t) v[Wh[x]].upd(1,1,Lant[Wh[x]].size(),poz[x],y);
        else
        {
            ans=-INF;
            while(Wh[x]!=Wh[y])
            {
                if(lvl[Father[Wh[x]]]<lvl[Father[Wh[y]]]) swap(x,y);
                ans=max(ans,v[Wh[x]].qry(1,1,Lant[Wh[x]].size(),poz[x],Lant[Wh[x]].size()));
                x=Father[Wh[x]];
            }
            ans=max(ans,v[Wh[x]].qry(1,1,Lant[Wh[x]].size(),min(poz[x],poz[y]),max(poz[x],poz[y])));
            cout<<ans<<"\n";
        }
    }
    return 0;
}