#include <iostream>
#include <fstream>

#define MAX_N 100005

using namespace std;

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

int n;
int m;

int values[MAX_N] = { 0 };
int tree[2 * MAX_N] = { 0 };

int queryResult = -1;

inline int Max(int a, int b)
{
	if (a > b)
		return a;

	return b;
}

void InsertTree(int node, int left, int right, int& a, int& b)
{
	if (left == right)
	{
		tree[node] = values[left];
	}
	else
	{
		int middle = (left + right) / 2;
		if (a <= middle)
		{
			InsertTree(node * 2, left, middle, a, b);
		}
		else
		{
			InsertTree((node * 2) + 1, middle + 1, right, a, b);
		}

		tree[node] = Max(tree[node * 2], tree[(node * 2) + 1]);
	}
}

void Query(int node, int left, int right, int& a, int& b)
{
	if (a <= left && right <= b)
	{
		queryResult = Max(queryResult, tree[node]);
	}
	else
	{
		int middle = (left + right) / 2;
		if (a <= middle)
		{
			Query(node * 2, left, middle, a, b);
		}

		if (b > middle)
		{
			Query((node * 2) + 1, middle + 1, right, a, b);
		}
	}
}

int main(void)
{
	fin >> n >> m;

	for (int i = 1; i <= n; i++)
	{
		fin >> values[i];
		InsertTree(1, 1, n, i, i);
	}

	for (int i = 1; i <= m; i++)
	{
		int task;
		int a, b;

		fin >> task >> a >> b;

		queryResult = -1;

		if (!task)
		{
			Query(1, 1, n, a, b);
			fout << queryResult << endl;
		}
		else
		{
			values[a] = b;

			InsertTree(1, 1, n, a, a);
		}
	}

	fin.close();
	fout.close();

	return 0;
}