#include <fstream>

using namespace std;
int aint[500005],n,p=1;
void up(int i, int val)
{
	int poz=p-1+i;
	aint[poz]=val;
	while(poz>1)
	{
		poz/=2;
		aint[poz]=max(aint[poz*2],aint[poz*2+1]);
	}
}
int query(int ind,int csta,int cdra,int cstq,int cdrq)
{
	if(cstq<=csta && cdra<=cdrq)
		return aint[ind];
	else
	{
        int aux=-1;
        if(cstq<=(csta+cdra)/2)
			aux=query(ind*2,csta,(csta+cdra)/2,cstq,cdrq);
		if(cdrq>(csta+cdra)/2)
			aux=max(aux,query(ind*2+1,(csta+cdra)/2+1,cdra,cstq,cdrq));
		return aux;
	}
}
int main()
{
	ifstream cin("arbint.in");
	ofstream cout("arbint.out");

	int m,c,a,b;
	cin>>n>>m;
	while(p<n)
		p*=2;
	for(int i=p;i<=p+n-1;i++)
	{
		cin>>aint[i];
	}
	for(int i=p-1;i>=1;i--)
	{
		aint[i]=max(aint[i*2],aint[i*2+1]);
	}

	for(int i=0;i<m;i++)
	{
		cin>>c>>a>>b;
		if(c==0)
			cout<<query(1,1,p,a,b)<<'\n';
		else
			up(a,b);
	}

    return 0;
}