#include <fstream>

using namespace std;

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

const int NMAX = 100002;

int N, Q;
int tree[4 * NMAX];

void Update( int nod, int lf, int rg, int pos, int val )
{
  if( lf == rg )
  {
    tree[nod] = val;
    return;
  }

  int mid = lf + ( rg - lf ) / 2;

  if( pos <= mid ) Update( nod * 2, lf, mid, pos, val );
  else Update( nod * 2 + 1, mid + 1, rg, pos, val );

  tree[nod] = max( tree[nod * 2], tree[nod * 2 + 1] );
}

int Query( int nod, int lf, int rg, int L, int R )
{
  if( L <= lf && rg <= R ) return tree[nod];

  int mid = lf + ( rg - lf ) / 2;
  int maxx = -1;

  if( L <= mid ) maxx = max( maxx, Query( nod * 2, lf, mid, L, R ) );
  if( mid < R ) maxx = max( maxx, Query( nod * 2 + 1, mid + 1, rg, L, R ) );

  return maxx;
}

void Read()
{
  int tip, a, b;

  fin >> N >> Q;

  for( int i = 1; i <= N; ++i )
  {
    fin >> a;

    Update( 1, 1, N, i, a );
  }

  for( int i = 1; i <= Q; ++i )
  {
    fin >> tip >> a >> b;

    if( tip == 0 ) fout << Query( 1, 1, N, a, b ) << '\n';
    else Update( 1, 1, N, a, b );
  }

}

int main()
{
    Read();

    return 0;
}