#include <fstream>
using namespace std;

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

const int N=500004;
int arb[N],m,n,mmax;

void mod(int nod,int p,int u,int x,int y)
{
	int m;
	if(u==p)
	{
		arb[nod]=y;
		return;
	}
	m=(p+u)/2;
	if(x<=m)
		mod(nod*2,p,m,x,y);
	else
		mod(nod*2+1,m+1,u,x,y);
	if(arb[nod*2]>=arb[nod*2+1])
		arb[nod]=arb[nod*2];
	else
		arb[nod]=arb[nod*2+1];
}

void cauta(int nod,int p,int u,int x,int y)
{
	int m;
	if(x<=p && u<=y)
	{
		if(arb[nod]>mmax)
			mmax=arb[nod];
		return ;
	}
	m=(p+u)/2;
	if(x<=m)
		cauta(nod*2,p,m,x,y);
	if(m<y)
		cauta(nod*2+1,m+1,u,x,y);
}

int main()
{
	int n,m,x,i,a,b;
	in>>n>>m;
	for(i=1;i<=n;i++)
	{	
		in>>x;
		mod(1,1,n,i,x);
	}
	for(i=1;i<=m;i++)
	{
		in>>x>>a>>b;
		if(x==0)
		{
			mmax=-1;
			cauta(1,1,n,a,b);
			out<<mmax<<"\n";
		}
		else
			mod(1,1,n,a,b);
	}
	
	return 0;
}