#include <fstream>
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int H[400001], n, m, sol, t, x, y;
void update(int n, int l, int r, int p, int v) {
    if (l >= r) { H[n] = v; return; }
    int m = (l + r) >> 1;
    if (p <= m) update (n << 1, 1, m, p, v);
    else update((n << 1) | 1, m + 1, r, p, v);
    H[n] = max(H[n << 1], H[(n << 1) | 1]);
}
void query(int n, int l, int r, int a, int b) {
    if (a <= l && r <= b) { sol = max(sol, H[n]); return;}
    int m = (l + r) >> 1;
    if (a <= m) query(n << 1, l, m, a, b);
    if (b > m) query((n << 1) | 1, m + 1, r, a, b);
}
int main()
{
    f >> n >> m;
    for (int i = 1; i <= n; ++i) {
        f >> x;
        update(1,1,n,i,x);
    }
    for (int i = 1; i <= m; ++i) {
        f >> t >> x >> y;
        if (t) update(1,1,n,x,y);
        else {
            sol = 0;
            query(1,1,n,x,y);
            g << sol << endl;
        }
    }
    return 0;
}