#include <fstream>
#include <cstdlib>
#define N_MAX 290000

using namespace std;
typedef unsigned int uint;

uint Arbint[N_MAX];

inline uint _max( uint x, uint y ) { return x >= y ? x : y; }
inline void Update( uint vertex, uint left, uint right, uint& xIndex, uint& xValue )
{
	if( left == right )
	{
		Arbint[vertex]=xValue;
	}
	else {
			uint middle=(left+right)>>1, next=vertex<<1;
			
			if( xIndex <= middle )
				Update( next, left, middle, xIndex, xValue );
			else Update( next|1, middle+1, right, xIndex, xValue );
			Arbint[vertex]=_max( Arbint[next], Arbint[next|1] );
		 }
}
inline uint Query( uint vertex, uint left, uint right, uint& sInt, uint& eInt )
{
	if( sInt <= left && eInt >= right )
		return Arbint[vertex];
	
	uint middle=(left+right)>>1, next=vertex<<1, a=0, b=0;
	
	if( sInt <= middle )
		a=Query( next, left, middle, sInt, eInt );
	if( eInt > middle )
		b=Query( next|1, middle+1, right, sInt, eInt );
	return _max( a, b );
}
int main()
{
	uint N, M, i, x, a, b, op;
	ifstream in( "arbint.in" );
	ofstream out( "arbint.out" );
	
	in>>N>>M;
	for( i=1; i <= N; ++i )
	{
		in>>x;
		Update( 1, 1, N, i, x );
	}
	for( ; M; --M )
	{
		in>>op>>a>>b;
		if( 1 == op )
			Update( 1, 1, N, a, b );
		else out<<Query( 1, 1, N, a, b )<<'\n';
	}
	
	return EXIT_SUCCESS;
}