#include <bits/stdc++.h>
#define lim 100005
#define mx 10000000000
using namespace std;

ifstream in("arbint.in");
ofstream out("arbint.out");

int n, m, v[lim], q[lim*5];

void make_tree(int start, int stop, int position)
{
    if(start==stop)
    {
        q[position]=v[start];
        return;
    }
    int mid=(start+stop)/2;
    make_tree(start, mid, 2*position);
    make_tree(mid+1, stop, 2*position+1);
    q[position]=max(q[2*position],q[2*position+1]);
}

void read()
{
    in>>n>>m;
    for(int i=1; i<=n; ++i)
    {
        in>>v[i];
    }
}

int get_max_tree(int start, int stop, int interval_start, int interval_stop, int position)
{
    if(interval_start<=start && interval_stop>=stop)
    {
        return q[position];
    }
    else if(interval_stop<start || interval_start>stop)
    {
        return -1;
    }
    int mid=(start+stop)/2;
    return max(get_max_tree(start, mid, interval_start, interval_stop, 2*position), get_max_tree(mid+1, stop, interval_start, interval_stop, 2*position+1));

}

void update_tree(int start, int stop, int nod, int position)
{
    if(start==stop)
    {
        q[position]=v[nod];
        return;
    }
    int mid=(start+stop)/2;
    if(nod<=mid)
    {
        update_tree(start, mid, nod, 2*position);
    }
    else
    {
        update_tree(mid+1, stop, nod, 2*position+1);
    }
    q[position]=max(q[2*position], q[2*position+1]);
}

void solve()
{
    int operation, sta, fin;
    make_tree(1, n, 1);
    for(int i=1; i<=m; ++i)
    {
        in>>operation>>sta>>fin;
        if(operation==0)
        {
            out<<get_max_tree(1, n, sta, fin, 1)<<'\n';
        }
        else if(operation==1)
        {
            v[sta]=fin;
            update_tree(1, n, sta, 1);
        }
    }
}

int main()
{
    read();
    make_tree(1, n, 1);
    solve();
    return 0;
}