#include <bits/stdc++.h>
using namespace std;

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

const int N = 1 << 18;
int a, b, poz, val, t[N], n, m, r;
int inf = 1 << 30;

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;
    r = -inf;


    if(a <= m) r = max(r, interogare(2 * p, st, m));

    if(b > m) r = max(r, interogare(2 * p + 1, m + 1, dr));

    return r;

}

int main()
{
    int i;

    fin >> n >> m;

    for(i = 1; i <= n; i++)
    {
        fin >> val;
        poz = i;
        actualizare(1, 1, n);
    }

    bool op;
    for (int i = 0; i < m; ++i)
    {
        fin >> op;
        if (!op)
        {
            fin >> a >> b;
            fout << interogare(1, 1, n) << '\n';
        }
        else
        {
            fin >> poz >> val;
            actualizare(1, 1, n);
        }
    }
    return 0;
}