#include <fstream>
using namespace std;

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

int n, m, v[100001], a[400001];

void build(int nod, int s, int d)
{
    if (s == d)
    {
        a[nod] = v[s];
        return;
    }
    int m = (s + d) / 2;
    build(nod * 2, s, m);
    build(nod * 2 + 1, m + 1, d);
    a[nod] = max(a[nod * 2], a[nod * 2 + 1]);
}

void update(int nod, int s, int d, int poz, int val)
{
    if (s == d)
    {
        a[nod] = val;
        return;
    }
    int m = (s + d) / 2;
    if (poz <= m)
        update(nod * 2, s, m, poz, val);
    else
        update(nod * 2 + 1, m + 1, d, poz, val);
    a[nod] = max(a[nod * 2], a[nod * 2 + 1]);
}

int query(int nod, int s, int d, int l, int r)
{
    if (d < l || s > r)
        return -1;

    if (l <= s && d <= r)
        return a[nod];

    int m = (s + d) / 2;
    return max(query(nod * 2, s, m, l, r), query(nod * 2 + 1, m + 1, d, l, r));
}

int main()
{
    f >> n >> m;

    for (int i = 1; i <= n; i++)
        f >> v[i];

    build(1, 1, n);

    int tip, x, y;
    for (int i = 1; i <= m; i++)
    {
        f >> tip >> x >> y;

        if (tip == 1)
        {
            update(1, 1, n, x, y);
        }
        else
        {
            g << query(1, 1, n, x, y) << '\n';
        }
    }

    return 0;
}