#include<cstdio>
#include<algorithm>
#define NMAX 100000+5
using namespace std;
struct nod
{
    int V,St,Dr;
    nod *FS,*FD,*T;
};
nod *root;
nod *point[NMAX];
int N,M,V[NMAX],A,B;
nod* do_tree(nod* T,int L,int R)
{
    nod* ret=new nod;
    ret->St=L;
    ret->Dr=R;
    ret->T=T;
    if(L==R)
    {
        ret->V=V[L];
        point[L]=ret;
        return ret;
    }
    int M=(L+R)/2;
    ret->FS=do_tree(ret,L,M);
    ret->FD=do_tree(ret,M+1,R);
    ret->V=max(ret->FS->V,ret->FD->V);
    return ret;
}
void update(int i,int x)
{
    V[i]=x;
    point[i]->V=x;
    for(nod* q=point[i]->T;q;q=q->T) q->V=max(q->FS->V,q->FD->V);
}
int query(nod* T)
{
    int st=(T->St),dr=(T->Dr);
    if(A<=st && dr<=B) return (T->V);
    if(A>dr || st>B) return 0;
    return max(query(T->FS),query(T->FD));
}
int main()
{
    int i,a,b,t;
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&N,&M);
    for(i=1;i<=N;i++) scanf("%d",&V[i]);
    root=do_tree(root,1,N);
    for(;M;--M)
    {
        scanf("%d%d%d",&t,&a,&b);
        if(t==1)
        {
            update(a,b);
            continue;
        }
        A=a; B=b;
        printf("%d\n",query(root));
    }
    return 0;
}