#include <algorithm>
#include <fstream>
#include <iostream>
using namespace std;

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

int H[400001], n, m, sol, t, x, y;
int a[100001];

void update(int n, int left, int right, int p, int v) {
    if (left >= right) {
        H[n] = v;
        return;
    }
    int m = (left + right) / 2;

    if (p <= m)
        update(2 * n, left, m, p, v);
    else
        update(2 * n + 1, m + 1, right, p, v);

    H[n] = max(H[2 * n], H[2 * n + 1]);
}

int query(int n, int left, int right, int ql, int qr) {
    if (ql <= left && right <= qr) {
        return H[n];
    }

    int m = (left + right) / 2;
    int result = 0;

    if (ql <= m)
        result = max(result, query(2 * n, left, m, ql, qr));

    if (qr > m)
        result = max(result, query(2 * n + 1, m + 1, right, ql, qr));

    return result;
}

void build(int n, int l, int r) {
    if (l >= r) {
        H[n] = a[l];
        return;
    }
    int m = (l + r) / 2;
    build(2 * n, l, m);
    build(2 * n + 1, m + 1, r);
    H[n] = max(H[2 * n], H[2 * n + 1]);
}

int main() {
    f >> n >> m;
    for (int i = 1; i <= n; ++i) {
        f >> a[i];
        /// update(1, 1, n, i, x);
    }
    build(1, 1, n);

    for (int i = 1; i <= m; ++i) {
        f >> t >> x >> y;
        if (t)
            update(1, 1, n, x, y);
        else {
            g << query(1, 1, n, x, y) << endl;
        }
    }

    return 0;
}