#include <fstream>

using namespace std;

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

const int N = 1 << 18;
const int INF = 1e9;
int n, M, m, t[N], val, a, b, poz, op;

void actualizare(int p, int st, int dr)
{
    if(st == dr)
    {
        t[p] = val;
        return;
    }

    m = (st + dr) / 2;

    if(poz <= m)
    {
        actualizare(2*p, st, m);
    }
    else{
        actualizare(2*p+1, m+1, dr);
    }
    t[p] = max(t[2*p], t[2*p+1]);
}

int interogare(int p, int st, int dr)
{
    if(a <= st && dr <= b)
    {
        return t[p];
    }

    int m = (st + dr) / 2;
    int m1 = -INF;
    int m2 = -INF;

    if(a <= m)
    {
        m1 = interogare(2*p, st, m);
    }
    if(b > m)
    {
        m2 = interogare(2*p+1, m+1, dr);
    }

    return max(m1, m2);

}

int main()
{
    in>>n>>M;
    for (int i = 1; i <= n; i++)
    {
        in >> val;
        poz = i;
        actualizare(1, 1, n);
    }
    for(int i=1; i<=M; i++)
    {
        in>>op;
        if(op == 0)
        {
            in>>a>>b;
            out<<interogare(1, 1, n)<<'\n';
        }
        else
        {
            in>>poz>>val;
            actualizare(1, 1, n);
        }
    }
    return 0;
}