#include <bits/stdc++.h>
#define nl '\n'
#define N 500000
using namespace std;
ifstream in("arbint.in");
ofstream out("arbint.out");
int values[N], seg_tree[4 * N], n, q;
void build(int node, int left, int right)
{
    if (left == right) {
        seg_tree[node] = values[left];
    }
    else {
        int middle = (left + right) / 2;

        build(node * 2, left, middle);
        build(node * 2 + 1, middle + 1, right);

        seg_tree[node] = std::max(seg_tree[node * 2],
                                    seg_tree[node * 2 + 1]);
    }
}

void update(int node, int left, int right, int position, int new_value)
{
    if (left == right) {
        seg_tree[node] = new_value;
    }
    else {
        int middle = (left + right) / 2;

        if (position <= middle)
            update(node * 2, left, middle, position, new_value);
        else
            update(node * 2 + 1, middle + 1, right, position, new_value);

        seg_tree[node] = std::max(seg_tree[node * 2],
            seg_tree[node * 2 + 1]);
    }
}

int query(int node, int left, int right, int query_left, int query_right)
{
    if (query_left <= left and right <= query_right) {
        return seg_tree[node];
    }
    else {
        int middle = (left + right) / 2;

        if (query_right <= middle)
            return query(node * 2, left, middle, query_left, query_right);
        if (middle + 1 <= query_left)
            return query(node * 2 + 1, middle + 1, right, query_left, query_right);

        return std::max(query(node * 2, left, middle, query_left, query_right),
            query(node * 2 + 1, middle + 1, right, query_left, query_right));
    }
}
int main() {
	in >> n >> q;
	for (int i = 1; i <= n; i++)
		in >> values[i];
	build(1, 1, n);
	for (int i = 1; i <= q; i++) {
		int cer;
		in >> cer;
		if (cer == 0) {
			int st, dr;
			in >> st >> dr;
			out << query(1, 1, n, st, dr) << nl;
		}
		else {
			int node, val;
			in >> node >> val;
			update(1, 1, n, node, val);
		}
	
	}
	return 0;
}