#include <iostream>
#include <string>

using namespace std;

#define NM 100000

int ARB[3*NM], N, Q, ans;

void update (int nod, int st, int dr, int pos, int nr)
{
	if (st == dr)
	{
		ARB[nod] = nr;
		return;
	}	
	
	int mij = (st + dr)/2;
	
	if (pos <= mij) update (2 * nod, st, mij, pos, nr);
	else update (2 * nod + 1, mij + 1, dr, pos, nr);
	
	ARB[nod] = max(ARB[2 * nod], ARB[2 * nod + 1]);
}

void query (int nod, int st, int dr, int a, int b)
{
	if (a <= st && dr <= b)
	{
		ans = max (ans, ARB[nod]);
		return ;
	}	
	
	int mij = (st + dr)/2;
	
	if (a <= mij) query (2 * nod, st, mij, a, b);
	if (b >= mij + 1) query (2 * nod + 1, mij + 1, dr, a, b);
}

int main()
{
	int pos, nr, a, b, q;
	
	freopen ("arbint.in", "r", stdin);
	freopen ("arbint.out", "w", stdout);
	
	scanf ("%d %d", &N, &Q);
	
	for (int i = 1; i <= N; ++i)
	{
		scanf ("%d", &nr);
		update (1, 1, N, i, nr);
	}	
	
	while (Q--)
	{
		scanf ("%d", &q);
		
		if (q)
		{
			scanf ("%d %d", &pos, &nr);
			update (1, 1, N, pos, nr);
		}	
		else 
		{
			scanf ("%d %d", &a, &b);
			ans = 0;
			query (1, 1, N, a, b);
			printf ("%d\n", ans);
		}	
	}	
	
	return 0;
}