#include <fstream>

using namespace std;

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

int n, m;
const int q = 100010;
int arb[q * 4], v[q];

void build(int node, int left, int right)
{
	if (left == right)
	{
		arb[node] = v[left];
	}
	else
	{
		int m = (left + right) / 2;
		build(node * 2, left, m);
		build(node * 2 + 1, m + 1, right);
		arb[node] = max(arb[node * 2], arb[node * 2 + 1]);
	}
}

void update(int node, int left, int right, int p, int np)
{
	if (left == right)
	{
		arb[node] = np;
	}
	else
	{
		int m = (left + right) / 2;
		if (p <= m)
		{
			update(node * 2, left, m, p, np);
		}
		else
		{
			update(node * 2 + 1, m + 1, right, p, np);
		}
		arb[node] = max(arb[node * 2], arb[node * 2 + 1]);
	}
}

int querry(int node, int left, int right, int ql, int qr)
{
	if (ql <= left && qr >= right)
	{
		return arb[node];
	}
	else
	{
		int m = (left + right) / 2;
		if (qr <= m)
		{
			return querry(node * 2, left, m, ql, qr);
		}
		if (m + 1 <= ql)
		{
			return querry(node * 2 + 1, m + 1, right, ql, qr);
		}
		return max(querry(node * 2, left, m, ql, qr),
			querry(node * 2 + 1, m + 1, right, ql, qr));
	}
}

int main()
{
	cin >> n >> m;
	for (int i = 1; i <= n; i++)
	{
		cin >> v[i];
	}
	build(1, 1, n);
	while (m > 0)
	{
		m--;
		int s;
		cin >> s;
		if (s == 0)
		{
			int left, right;
			cin >> left >> right;
			cout << querry(1, 1, n, left, right) << endl;
		}
		else
		{
			int p, np;
			cin >> p >> np;
			update(1, 1, n, p, np);
		}
	}
}