# include <stdio.h>

int a[100005],is[300000],id[300000],st[300000],dr[300000],t[300000],p,u,n,mij,m[300000],x,y,maxf,i,l,k,q,sir[300000],no,maxim,ok;

void crearearb ()
{
is[1]=1;
id[1]=n;
p=1;
u=1;

  while (p<=u)
   {
    if (is[p]<id[p])
    {
    mij=(is[p]+id[p])/2;
    u++;
    t[u]=p;
    st[p]=u;
    is[u]=is[p];
    id[u]=mij;

    u++;
    t[u]=p;
    dr[p]=u;
    is[u]=mij+1;
    id[u]=id[p];

    }
     if (is[p]==id[p])
     {
     m[p]=a[is[p]];
     sir[is[p]]=p;
     }

     p++;

      }

      }


      void max (int nod)
      {

	  if (st[nod]!=0 || dr[nod]!=0)
	  {
	  max (st[nod]);
	  max (dr[nod]);
	  }
	  if (m[nod]==0)
	  if (m[st[nod]]>m[dr[nod]])
	  m[nod]=m[st[nod]];
	  else
	  m[nod]=m[dr[nod]];




	}


 void inter (int nod)

  {
   int mij;

   if (is[nod]>=x && id[nod]<=y)
   {

  if (maxf<m[nod])
   maxf=m[nod];
   }
   else
   {
   mij=(is[nod]+id[nod])/2;
   if (x<=mij)
   inter (st[nod]);

   if (y>mij)
   inter (dr[nod]);

   }


   }

    void schimba ()

    { no=sir[x];
       a[is[no]]=y;
       m[no]=y;
	ok=0;
	while (ok==0)
	{

	no=t[no];
	if (m[st[no]]>m[dr[no]])
	maxim=m[st[no]];
	else
	maxim=m[dr[no]];

	 if (maxim>m[no])
	  m[no]=maxim;

	 else
	 ok=1;

	}

	 }



int main ()
{
freopen ("arbint.in","r",stdin);
freopen ("arbint.out","w",stdout);
scanf ("%i%i",&n,&k);

 for (i=1;i<=n;i++)
  scanf ("%i",&a[i]);


  crearearb ();
  max (1);

  for (i=1;i<=k;i++)
  {
  scanf ("%i%i%i",&l,&x,&y);

  if (l==0)
  {
  maxf=-32000;

  if (x==y)
  maxf=a[x];

  else
  inter (1);

  printf ("%i\n",maxf);
  }
  else

  schimba ();

  }




  return 0;
  }