#include <bits/stdc++.h>

using namespace std;

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

const int INF = 1e9;
const int MAX = 1 << 18;

int t[MAX], a, b, poz, val;

void actualizare(int p, int st, int dr)
{
    if(st == dr)
    {
        t[p] = val;
        return;
    }
    int 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 maxst = -INF;
    int maxdr = -INF;
    if(a <= m)
    {
        maxst = interogare(2 * p, st, m);
    }
    if(b > m)
    {
        maxdr = interogare(2 * p + 1, m + 1, dr);
    }
    return max(maxst, maxdr);
}

int main()
{
    int n, m, op;
    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;
}