#include <bits/stdc++.h>

using namespace std;
ifstream fin ("arbint.in");
ofstream fout ("arbint.out");
const int nmax = 100000 + 10;
int v[nmax], arb[4 * nmax];
void update (int node, int left, int right, int a, int b) {
    if (left == right) {
        arb[node] = b;
        return;
    }
    int mid = (left + right) / 2;
    if (a <= mid)
        update (node * 2, left, mid, a, b);
    if (a > mid)
        update (node * 2 + 1, mid + 1, right, a, b);
    arb[node] = max (arb[node * 2], arb[node * 2 + 1]);
}
int query (int node, int left, int right, int l, int r) {
    if (l <= left && right <= r) {
        return arb[node];
    }
    int mid = (left + right) / 2;
    int mx = -1;
    if (l <= mid)
        mx = max (mx, query(node * 2, left, mid, l, r));
    if (mid < r)
        mx = max (mx, query(node * 2 + 1, mid + 1, right, l, r));
    return mx;
}
void create (int node, int left, int right) {
    if (left == right) {
        arb[node] = v[left];
        return;
    }
    int mid = (left + right) / 2;
    create (node * 2, left, mid);
    create (node * 2 + 1, mid + 1, right);
    arb[node] = max (arb[node * 2], arb[node * 2 + 1]);
}
int main()
{
    int n, m;
    fin >> n >> m;
    for (int i = 1; i <= n; ++i) {
        fin >> v[i];
    }
    create (1, 1, n);
    for (int i = 1; i <= m; ++i) {
        int cerinta, a, b;
        fin >> cerinta >> a >> b;
        if (cerinta == 1) {
            update(1, 1, n, a, b);
            v[a] = b;
        }
        else {
            int maxim = query(1, 1, n, a, b);
            fout << maxim << '\n';
        }
    }
    return 0;
}