#include<cstdio>
#include<algorithm>
using namespace std;
const int MAXN=400005;
int n,m,maxim;
int arb[MAXN];
void update(int node, const int left, const int right, const int pos, const int val)
{
	if (left==right)
	{
		arb[node]=val;
		return;
	}
	int mid=left+(right-left)/2;
	if (pos<=mid)	update(node*2,left,mid,pos,val);
	else			update(node*2+1,mid+1,right,pos,val);

	arb[node]=max(arb[node*2],arb[node*2+1]);
}
void query(int node, const int left, const int right, const int a, const int b)
{
	if (a<=left && b>=right)
	{
		if (arb[node]>maxim)
			maxim=arb[node];
		return;
	}

	int mid=left+(right-left)/2;
	if (a<=mid)	query(node*2,left,mid,a,b);
	if (b>mid)	query(node*2+1,mid+1,right,a,b);
}
int main()
{
	int op,x,y;
	freopen("arbint.in","r",stdin);
	freopen("arbint.out","w",stdout);
	scanf("%d%d",&n,&m);
	for (int i=1; i<=n; ++i)
	{
		scanf("%d",&x);
		update(1,1,n,i,x);
	}
	for (int i=1; i<=m; ++i)
	{
		maxim=-1;
		scanf("%d%d%d",&op,&x,&y);
		if (!op)
		{
			query(1,1,n,x,y);
			printf("%d\n",maxim);
		}
		else
			update(1,1,n,x,y);
	}
	return 0;
}