#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>

using namespace std;

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

vector<int> arb;
vector<int> v;

void build(int i, int l, int r) {
    if (l == r)
        arb[i] = v[l];
    else {
        int mid = (l + r) / 2;
        build(i * 2, l, mid);
        build(i * 2 + 1, mid + 1, r);
        arb[i] = max(arb[i * 2], arb[i * 2 + 1]);
    }
}

void change(int i, int l, int r, int idx, int val) {
    if (l == r) {
        v[idx] = val;
        arb[i] = val;
    } else {
        int mid = (l + r) / 2;
        if (idx <= mid)
            change(i * 2, l, mid, idx, val);
        else
            change(i * 2 + 1, mid + 1, r, idx, val);
        arb[i] = max(arb[i * 2], arb[i * 2 + 1]);
    }
}

int query(int i, int l, int r, int ql, int qr) {
    if (qr < l || ql > r)
        return -1;
    if (ql <= l && qr >= r)
        return arb[i];
    int mid = (l + r) / 2;
    return max(query(i * 2, l, mid, ql, qr), query(i * 2 + 1, mid + 1, r, ql, qr));
}

int main() {
    int n, m;
    f >> n >> m;
    v.resize(n + 1);
    arb.resize(4 * n);

    for (int i = 1; i <= n; i++)
        f >> v[i];

    build(1, 1, n);

    for (int i = 1; i <= m; i++) {
        int choice, a, b;
        f >> choice >> a >> b;
        switch (choice) {
            case 0:
                g << query(1, 1, n, a, b) << endl;
                break;
            case 1:
                change(1, 1, n, a, b);
                break;
        }
    }

    f.close();
    g.close();

    return 0;
}