#include <bits/stdc++.h>
#define pb push_back
using namespace std;

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

int n, m;
int a[400005];
void build(int nod, int st, int dr)
{
    if (st == dr)
    {
        fin >> a[nod];
        return;
    }
    int mid = (st + dr) >> 1;
    build(nod << 1, st, mid);
    build(nod << 1 | 1, mid + 1, dr);
    a[nod] = max(a[nod << 1], a[nod << 1 | 1]);
}
void upd(int nod, int st, int dr, int p, int val)
{
    if (st == dr)
    {
        a[nod] = val;
    }
    else
    {
        int mid = (st + dr) >> 1;
        if (p <= mid)
            upd(nod << 1, st, mid, p, val);
        else
            upd(nod << 1 | 1, mid + 1, dr, p, val);
        a[nod] = max(a[nod << 1], a[nod << 1 | 1]);
    }
}
int qry(int nod, int st, int dr, int x, int y)
{

    if (st > dr || st > y || dr < x)
        return -1;
    if (st >= x && dr <= y)
        return a[nod];
    int mid = (st + dr) >> 1;
    int q1 = qry(nod << 1, st, mid, x, y);
    int q2 = qry(nod << 1 | 1, mid + 1, dr, x, y);
    return max(q1, q2);
}

int32_t main()
{
    fin >> n >> m;
    build(1, 1, n);
    while (m--)
    {

        int op, x, y;
        fin >> op >> x >> y;
        if (op == 0)
        {

            fout << qry(1, 1, n, x, y) << '\n';
        }
        else
            upd(1, 1, n, x, y);
    }
    return 0;
}