#include <fstream>

using namespace std;

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

int n, m, i, a, b, t[400001];
bool op;

void update (int s, int st, int dr, int pos, int val)
{
    if (st == dr)
    {
        t[s] = val;
        return;
    }
    int m = (dr+st)/2, ps = 2*s, pd = 2*s+1;
    if (pos <= m)
        update (ps, st, m, pos, val);
    else
        update (pd, m+1, dr, pos, val);
    t[s] = max (t[ps], t[pd]);
}
int query (int s, int st, int dr, int a, int b)
{
    if (a <= st && dr <= b)
        return t[s];
    int m = (st+dr)/2, ps = 2*s, pd = 2*s+1, rs = -2e8, rd = -2e8;
    if (a <= m)
        rs = query(ps, st, m, a, b);
    if (b >= m+1)
        rd = query(pd, m+1, dr, a, b);
    return max(rd, rs);
}
int main()
{
    fin >> n >> m;
    for (i = 1; i <= n; i++)
    {
        fin >> a;
        update (1, 1, n, i, a);
    }
    for (i = 1; i <= m; i++)
    {
        fin >> op >> a >> b;
        if (op)
            update (1, 1, n, a, b);
        else
            fout << query(1, 1, n, a, b) << '\n';
    }
    return 0;
}