#include <algorithm>
using namespace std;

#define DIM 100005

int aint[DIM<<2];
int n,m,maxim;

inline int stg (int nod)
{
    return (nod<<1);
}

inline int drp (int nod)
{
    return ((nod<<1)|1);
}

void update (int nod,int st,int dr,int poz,int val)
{
    int mij;

    if (st==dr)
        aint[nod]=val;
    else
    {
        mij=(st+dr)/2;
        if (poz<=mij)
            update (stg (nod),st,mij,poz,val);
        else
            update (drp (nod),mij+1,dr,poz,val);
        aint[nod]=max (aint[stg (nod)],aint[drp (nod)]);
    }
}

void read ()
{
    int i,x;

    scanf ("%d%d",&n,&m);
    for (i=1; i<=n; ++i)
    {
        scanf ("%d",&x);
        update (1,1,n,i,x);
    }
}

void query (int nod,int st,int dr,int in,int sf)
{
    int mij;

    if (in<=st && dr<=sf)
        maxim=max (maxim,aint[nod]);
    else
    {
        mij=(st+dr)/2;
        if (in<=mij)
            query (stg (nod),st,mij,in,sf);
        if (mij<sf)
            query (drp (nod),mij+1,dr,in,sf);
    }
}

void solve ()
{
    int i,tip,x,y;

    for (i=1; i<=m; ++i)
    {
        scanf ("%d%d%d",&tip,&x,&y);
        if (!tip)
        {
            maxim=-1;
            query (1,1,n,x,y);
            printf ("%d\n",maxim);
        }
        else
            update (1,1,n,x,y);
    }
}

int main ()
{
    freopen ("arbint.in","r",stdin);
    freopen ("arbint.out","w",stdout);

    read ();
    solve ();

    return 0;
}