#include <fstream>

using namespace std;

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

int x,a,b,maxim,stanga,dreapta,val,poz,start,finish,n,m;
int arbore[400001];

void update(int nod,int stanga,int dreapta)
{
    if(stanga == dreapta)
    {
        arbore[nod] = val;
        return;
    }

    int mij = (stanga + dreapta) / 2;
    if(poz <= mij)
        update(2 * nod, stanga, mij);
    else
        update(2 * nod + 1,mij + 1,dreapta);

    arbore[nod] = max(arbore[2 * nod],arbore[2 * nod + 1]);
}

void query(int nod,int stanga, int dreapta)
{
    if(start <= stanga && dreapta <= finish)
    {
        if(maxim < arbore[nod]) maxim = arbore[nod];
        return;
    }

    int mij = (stanga + dreapta) / 2;
    if(start <= mij) query(2 * nod,stanga,mij);
    if(mij < finish) query(2 * nod + 1,mij + 1,dreapta);
}

int main()
{
    f >> n >> m;
    for(int i = 1; i <= m; i++)
    {
        f >> x;
        poz = i;
        val = x;
        update(1,1,n);
    }
    for(int i = 1; i <= m; i++)
    {
        f >> x >> a >> b;
        if(!x)
        {
            maxim = -1;
            start = a;
            finish = b;
            query(1,1,n);

            g << maxim << '\n';
        }
        else
        {
            poz = a;
            val = b;
            update(1,1,n);
        }
    }
    return 0;
}