#include <stdio.h>
#include <algorithm>

#define MAXN 100000

int v[MAXN], aint[MAXN * 2];

void construct( int l, int r, int node ) {
  int leftChild, rightChild, middle;
  middle = (r + l) / 2;
  leftChild = node + 1;
  rightChild = node + 2 * ( middle - l + 1 );

  if( l == r )
    aint[node] = v[l - 1];
  else {
    construct( l, middle, leftChild );
    construct( middle + 1, r, rightChild );
    aint[node] = std::max( aint[leftChild], aint[rightChild] );
  }
}

int getMax( int a, int b, int l, int r, int node ) {
  if( l == a && r == b )
    return aint[node];

  int leftChild, rightChild, middle, mx;
  middle = (r + l) / 2;
  leftChild = node + 1;
  rightChild = node + 2 * ( middle - l + 1 );

  mx = 0;
  if( a <= middle )
    mx = std::max( mx, getMax( a, std::min( middle, b ), l, middle, leftChild ));
  if( b > middle )
    mx = std::max( mx, getMax( std::max( middle + 1, a ), b, middle + 1, r, rightChild ));

  return mx;
}

void update( int l, int r, int node, int pos, int val ) {
  if( l == r ) {
    aint[node] = val;
    return;
  }

  int leftChild, rightChild, middle, mx;
  middle = (r + l) / 2;
  leftChild = node + 1;
  rightChild = node + 2 * ( middle - l + 1 );

  if( pos <= middle )
    update( l, middle, leftChild, pos, val );
  else
    update( middle + 1, r, rightChild, pos, val );

  aint[node] = std::max( aint[leftChild], aint[rightChild] );
}

int main() {
  FILE *fin, *fout;
  int n, m, i, a, b, op;
  fin = fopen( "arbint.in", "r" );

  fscanf( fin, "%d%d", &n, &m );
  for( i = 0; i < n; i++ )
    fscanf( fin, "%d", &v[i] );

  construct(1, n, 0);

  fout = fopen( "arbint.out", "w" );

  for( i = 0; i < m; i++ ) {
    fscanf( fin, "%d%d%d", &op, &a, &b );
    if( op == 0 )
      fprintf( fout, "%d\n", getMax(a, b, 1, n, 0) );
    else
      update( 1, n, 0, a, b );
  }

  fclose( fin );
  fclose( fout );
  return 0;
}