#include <bits/stdc++.h>
#define maxn 100000
#define maxl2 17
#define fi first
#define se second

using namespace std;

struct nod
{
  int st, dr, _M;
};

nod aint[maxn*maxl2+5];
int v[maxn+5];
int ans;

void build ( int i, pair<int,int> itv )
{
  aint[i].st = itv.fi;
  aint[i].dr = itv.se;
  aint[i]._M = 0;
  if ( itv.fi == itv.se )
    aint[i]._M = v[itv.fi];
  else if ( itv.fi < itv.se )
  {
    int mid = (itv.fi+itv.se) / 2;
    build ( i * 2, {itv.fi,mid} );
    build ( i * 2 + 1, {mid+1,itv.se} );
    aint[i]._M = max ( aint[i*2]._M, aint[i*2+1]._M );
  }
}

void update ( int poz, int i, pair<int,int> itv )
{
  if ( poz < itv.fi || poz > itv.se ) return;
  if ( itv.fi == itv.se )
    aint[i]._M = v[poz];

  int mid = (itv.fi+itv.se) / 2;
  if ( itv.fi < itv.se )
  {
    update ( poz, i * 2, {itv.fi, mid} );
    update ( poz, i * 2 + 1, {mid+1, itv.se} );
  }

  aint[i]._M = max ( aint[i*2]._M, aint[i*2+1]._M );
}

void query ( int i, pair<int,int> cur, pair<int,int> itv )
{
  if ( cur.fi > cur.se || cur.se < itv.fi || cur.fi > itv.se ) return;

  if ( cur.fi >= itv.fi && cur.se <= itv.se )
  {
    ans = max ( ans, aint[i]._M );
    return;
  }

  if ( cur.fi < cur.se )
  {
    int mid = (cur.fi+cur.se) / 2;
    query ( i * 2, {cur.fi,mid}, itv );
    query ( i * 2 + 1, {mid+1,cur.se}, itv );
  }
}

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

  int n, t;
  fin >> n >> t;

  int i;
  for ( i = 1; i <= n; i++ )
    fin >> v[i];

  build ( 1, {1,n} );

  int id, a, b;
  while (t--)
  {
    fin >> id >> a >> b;
    if ( id == 0 )
    {
      ans = 0;
      query ( 1, {1,n}, {a,b} );
      fout << ans << '\n';
    }
    else
    {
      v[a-1] = b;
      update ( a, 1, {1,n} );
    }
  }

  fin.close ();
  fout.close ();

  return 0;
}