#include<stdio.h>
#define Nmx 1000001

int max[4*Nmx+66];
int pos,val,start,n,m,finish, maxim;

int Maxim(int a,int b)
{
	if(a>b) return a;
	else return b;
}

void update(int nod,int left,int right)
{
	if(left==right)
	{
		max[nod]=val;
		return ;
	}
	int div=(left+right)/2;
	if(pos<=div) update(2*nod,left,div);
	  else update(2*nod+1,div+1,right);
	max[nod] = Maxim( max[2*nod], max[2*nod+1] );
}

void query(int nod,int left,int right)
{
	if(start<=left&&right<=finish)
	{
		if(maxim<max[nod]) maxim=max[nod];
		return ;
	}
	int div=(left+right)/2;
    if ( start <= div ) query(2*nod,left,div);  
    if ( div < finish ) query(2*nod+1,div+1,right);  \
}

int main()
{
	int x,a,b;
	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);
		pos=i;val=x;
		update(1,1,n);
	}
	for(int i=1;i<=m;i++)
	{
		scanf("%d %d %d",&x,&a,&b);
		if(x==0)
		{
			 maxim = -1;  
             start = a; finish = b;  
             query(1,1,n);                  
             printf("%d\n", maxim); 
		}
		else
		{
			pos=a;val=b;
			update(1,1,n);
		}
	}
	return 0;
}