#include <fstream>
#include <algorithm>
#include <vector>
#include <cstring>

#define oo 0x3f3f3f3f
#define NMAX 100005
#define get_max(a,b) ((a)>(b)?(a):(b))
#define get_min(a,b) ((a)<(b)?(a):(b))

using namespace std;

int Answer;

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

class AINT 
{
private:
	int V[4*NMAX] ;
public:
	void Update ( int Node , int Left , int Right , int Pos  , int Value )
	{
		if ( Left == Right ) 
		{
			this->V[Node] = Value ;
			return ;
		}
		int Middle = ( Left + Right ) >> 1;
		if ( Middle < Pos )	Update( 2*Node +1  , Middle +1 , Right , Pos , Value );
        else Update ( 2* Node , Left , Middle , Pos , Value );
		this->V[Node] = get_max ( this->V[2*Node+1] , this->V[2*Node] );
	}
	void Query ( int Node , int Left , int Right , int SearchLeft , int SearchRight )
	{
			if ( SearchLeft <= Left and Right <= SearchRight )
			{
				Answer = get_max ( Answer , this->V[Node] );
				return ;
			}
			int Middle = ( Left + Right ) >> 1;
			if ( SearchLeft <= Middle )
				Query ( 2*Node , Left , Middle , SearchLeft , SearchRight );
			if ( Middle < SearchRight )
				Query ( 2*Node + 1 , Middle + 1 , Right , SearchLeft , SearchRight ) ;
	}
};
int N , M ;
AINT  A;
int main ( void )
{
	int i , j , type  , x , y;
	in >> N >> M ;
	for ( i = 1 ; i <= N ; ++i )
     in >> x , A.Update ( 1 , 1 , N , i , x);
	for ( i = 1 ; i <= M ; ++i )
	{
		in >> type  >> x >> y ;
		( type == 1 ? A.Update ( 1 , 1 , N ,  x , y ) : A.Query ( 1 , 1 , N , x , y ) ); 
		if ( not type == 1 )out << Answer << "\n";
		Answer = -oo;
	}
	in.close();
	out.close();
	return 0;
}