#include <bits/stdc++.h>

using namespace std;

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

int a[400005];

void update (int nod, int st, int dr, int pos, int x)
{
    if (st == dr)
    {
        a[nod] = x;
        return;
    }

    int mid = (st + dr) / 2;

    if (pos <= mid)
        update(2*nod, st, mid, pos, x);
    else
        update(2*nod+1, mid+1, dr, pos, x);

    a[nod] = max(a[2*nod], a[2*nod+1]);
}

int query (int nod, int st, int dr, int l, int r)
{
    if (l <= st && dr <= r)
        return a[nod];

    int mid = (st + dr) / 2;

    int maxim = -1;
    if (l <= mid)
        maxim = max(maxim, query(2*nod, st, mid, l, r));
    if (mid < r)
        maxim = max(maxim, query(2*nod+1, mid+1, dr, l, r));

    return maxim;
}

int main()
{
    int n, q;
    in >> n >> q;

    for (int i=1; i<=n; i++)
    {
        int x;
        in >> x;

        update(1, 1, n, i, x);
    }

    while (q--)
    {
        int op, x, y;
        in >> op >> x >> y;

        if (op == 0)
            out << query(1, 1, n, x, y) << '\n';
        else
            update(1, 1, n, x, y);
    }

    return 0;
}