#include <fstream>
using namespace std;
 
ifstream in ("arbint.in");
ofstream out ("arbint.out");
 
int n, m, v[100005];
int aint[400005];
 
void build (int nod, int s, int d)
{
    if (s == d) {
        aint[nod] = v[s];
        return;
    }
    int m = (s + d) / 2;
    build(nod * 2, s, m);
    build(nod * 2 + 1, m + 1, d);
    aint[nod] = max(aint[nod * 2], aint[nod * 2 + 1]);
}
 
void update (int nod, int s, int d, int pos, int val)
{
    if (s == d) {
        aint[nod] = val;
        return;
    }
    int m = (s + d) / 2;
    if (pos <= m)
        update (nod * 2, s, m, pos, val);
    else
        update (nod * 2 + 1, m + 1, d, pos, val);
    aint[nod] = max (aint[nod * 2], aint[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 aint[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()
{
    in >> n >> m;
 
    for (int i = 1; i <= n; i++)
        in >> v[i];
 
    build (1, 1, n);
 
    int tip, x, y;
    for (int i = 1; i <= m; i++) {
        in >> tip >> x >> y;
        if (tip == 1) {
            update(1, 1, n, x, y);
        } else {
            out << query(1, 1, n, x, y) << '\n';
        }
    }
    return 0;
}