#include <fstream>

using namespace std;

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

int n,m,poz,val,start,finish,arb[4*100019],maxim;

int max(int x,int y)
{
    if(x > y)
        return x;
    return y;
}

void create(int,int,int);
void query(int,int,int);

int main()
{
    int a,b,x,i;
    in >> n >> m;
    for(i = 1 ; i<= n ; i++)
    {
        in >> x;
        poz = i;
        val = x;
        create(1,1,n);
    }
    for(i = 1 ; i <= m ; i++)
    {
        in >> x >> a >> b;
        if(x == 0)
        {
            maxim = -1;
            start = a;
            finish = b;
            query(1,1,n);
            out << maxim << "\n";
        }
        else
        {
            poz = a;
            val = b;
            create(1,1,n);
        }
    }
}

void create(int nod,int st,int dr)
{
    int m;
    if(st == dr)
    {
        arb[nod] = val;
        return;
    }
    else
    {
        m = (st + dr)/2;
        if(poz <= m)
            create(nod*2,st,m);
        else
            create(nod*2+1,m+1,dr);
        arb[poz] = max(arb[nod*2],arb[nod*2+1]);
    }
}

void query(int nod,int st,int dr)
{
    int m;
    if(start << st && dr <= finish)
    {
        if(maxim < arb[nod])
            maxim = arb[nod];
        return;
    }
    m = (st + dr)/2;
    if(start <= m)
        query(2*nod,st,m);
    if(m < finish)
        query(2*nod+1,m+1,dr);
}