#include <cmath>
#include <fstream>

using namespace std;

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

#define MAX 100001

int n, m, x, y, c, l, k;
int b[MAX], a[MAX];
int St[MAX], Dr[MAX];

void add()
{
     a[x] = y;
     for (int i = 1; i * l <= n; i++)
         if (x >= l * (i - 1) + 1 && x <= l * i )
         {
              b[i] = -1;
              for (int nod = l * (i-1) + 1; nod <= l*i; nod++)
                  b[i] = max(b[i], a[nod]);

              break;
         }
}

int query()
{
    int mx = -1;
    int st = (1<<30), dr=-1;

    for (int i = 1; i <= k; i++)
    {
        if (x <= St[i] && Dr[i] <= y)
        {
             if (St[i] < st)  st = St[i];
             if (Dr[i] > dr)  dr = Dr[i];
             mx = max(mx, b[i]);
        }
        if (Dr[i] > y) break;
    }

    if (st == (1<<30) && dr == -1) st = dr = y;

    for (int i = x; i <= st; i++)
        mx = max(mx, a[i]);

    for (int i = dr; i <= y; i++)
        mx = max(mx, a[i]);

    return mx;
}
int main()
{
    fin >> n >> m;
    for (int i = 1; i <= n; i++)
        fin >> a[i];

    l = sqrt(n);
    k = n/l + 1;

    for (int i = 1; i * l <= n; i++)
    {
        b[i] = -1;
        St[i] = l*(i-1)+1;
        Dr[i] = l*i;

        for (int nod = St[i]; nod <= Dr[i]; nod++)
            b[i] = max(b[i], a[nod]);
    }

    for (int i = 1; i <= m; i++)
    {
        fin >> c >> x >> y;

        if (c) add();
        else fout << query() << '\n';
    }
    return 0;
}