#include <iostream>
#include <fstream>
using namespace std;

int a[100000], d[400000];

void creare(int nod, int st, int dr)
{
    if(st == dr)
    {
        d[nod] = a[st];
        return;
    }
    creare(nod * 2, st, (st + dr) / 2);
    creare(nod * 2 + 1, (st + dr) / 2 + 1, dr);
    d[nod] = max(d[nod * 2], d[nod * 2 + 1]);
}

void modif(int nod, int st, int dr, int i, int val)
{
    if(i < st || i > dr) return;
    if(st == dr)
    {
        d[nod] = val;
        return;
    }
    modif(nod * 2, st, (st + dr) / 2, i, val);
    modif(nod * 2 + 1, (st + dr) / 2 + 1, dr, i, val);
    d[nod] = max(d[nod * 2], d[nod * 2 + 1]);
}

int maxim(int nod, int st, int dr, int i, int j)
{
    if(dr < i || st > j) return 0;
    if(i <= st && dr <= j) return d[nod];
    return max(maxim(nod * 2, st, (st + dr) / 2, i, j), maxim(nod * 2 + 1, (st + dr) / 2 + 1, dr, i, j));
}

int main()
{int n, m, i, x, y, o;
ifstream f("arbint.in");
ofstream g("arbint.out");
f >> n >> m;
for(i = 1; i <= n; i++)
    f >> a[i];
creare(1, 1, n);
for(i = 0; i < m; i++)
{
    f >> o >> x >> y;
    if(o) modif(1, 1, n, x, y);
    else g << maxim(1, 1, n, x, y) << '\n';
}
f.close();
g.close();
return 0;
}