#include <fstream>
#include <algorithm>

using namespace std;

const int NMAX = 100010;
int v[NMAX], aint[4 * NMAX];
int n, m;
int answer;

inline int LeftSon(const int &x)
{
	return x * 2;
}

inline int RightSon(const int &x)
{
	return 2 * x + 1;
}

inline int Father(const int &x)
{
	return x / 2;
}

void Build(int nod, int left, int right)
{
	if (left == right)
	{
		aint[nod] = v[left];
		return;
	}
	int mij = (left + right) / 2;
	Build(LeftSon(nod), left, mij);
	Build(RightSon(nod), mij + 1, right);
	aint[nod] = max(aint[LeftSon(nod)], aint[RightSon(nod)]);
}

void Update(int nod, int left, int right, const int &poz, const int &val)
{
	if (left == right)
	{
		aint[nod] = val;
		v[poz] = val;
		return;
	}
	int mij = (left + right) / 2;
	if (poz <= mij)
		Update(LeftSon(nod), left, mij, poz, val);
	else
		Update(RightSon(nod), mij + 1, right, poz, val);
	aint[nod] = max(aint[LeftSon(nod)],aint[RightSon(nod)]);
}

void Query(int nod, int left, int right, const int &LeftQuery, const int &RightQuery)
{
	if (LeftQuery <= left && right <= RightQuery)
	{
		answer = max(answer, aint[nod]);
		return;
	}
	int mij = (left + right) / 2;
	if (LeftQuery <= mij)
		Query(LeftSon(nod),left,mij,LeftQuery,RightQuery);
	if (RightQuery >= mij + 1)
		Query(RightSon(nod), mij + 1, right, LeftQuery, RightQuery);

}

int main()
{
	ifstream f("arbint.in");
	ofstream g("arbint.out");
	f >> n >> m;
	for (int i = 1;i <= n;i++)
		f >> v[i];
	Build(1, 1, n);
	for (int i = 1;i <= m;i++)
	{
		int x, a, b;
		f >> x >> a >> b;
		switch (x)
		{
			case 0:
				answer = -1;
				Query(1,1,n,a,b);
				g << answer << "\n";
				break;
			case 1:
				Update(1,1,n,a,b);
				break;
		}
	}
	f.close();
	g.close();
	return 0;
}