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

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

/*
	tree memory = 2^(k + 1) - (2^k - n) - 1
	k = min so that 2^k >= n
 */

const int Nmax = 100005;
const int tree_size = 262144;

int n, m;
int op, a, b;
int tree[tree_size];
int position, value, result;

void update(int node, int l, int r) {
	if (l == r) {
		tree[node] = value;
		if (node >= tree_size) out << "Problem 1 " << node << '\n';
	}
	else {
		int m = (l + r) / 2;
		if (position <= m) update(node * 2, l, m);
		else update(node * 2 + 1, m + 1, r);
		if (node >= tree_size) out << "Problem 2 " << node << '\n';
		tree[node] = max(tree[node * 2], tree[node * 2 + 1]);
	}
}

void query(int node, int l, int r) {
	if (a <= l && r <= b) {
		if (node >= tree_size) {
			out << "Problem 3 " << node << ' ' << l << ' ' << r << '\n';
		}
		result = max(result, tree[node]);
	}
	else {
		int m = (l + r) / 2;
		if (a <= m) query(node * 2, l, m);
		if (m < b) query(node * 2 + 1, m + 1, r);
	}
}

int main() {
	in >> n >> m;
	for (int i = 1; i <= n; ++i) {
		in >> a;
		position = i;
		value = a;
		update(1, 1, n);
	}
	for (int i = 1; i <= m; ++i) {
		in >> op >> a >> b;
		if (op == 0) {
			result = -1;
			query(1, 1, n);
			out << result << '\n';
		}
		else {
			position = a;
			value = b;
			update(1, 1, n);
		}
	}
	return 0;
}