#include <fstream>

using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");

const int N_MAX = 700010;
int n, i, x, q, poz, maxi, val, a, b, start, finish, tree[N_MAX];

static inline void Update(int nod, int st, int dr)
{
    if (st == dr)
    {
        tree[nod] = val;
        return;
    }
    int m = (st + dr) / 2;
    if (poz <= m)
        Update(2 * nod, st, m);
    else
        Update(2 * nod + 1, m + 1, dr);
    tree[nod] = max(tree[2 * nod], tree[2 * nod + 1]);
}

static inline void Query(int nod, int st, int dr)
{
    if (start <= st && finish >= dr)
    {
        if (tree[nod] > maxi)
            maxi = tree[nod];
        return;
    }
    int m = (st + dr) / 2;
    if (start <= m)
        Query(2 * nod, st, m);
    if (m < finish)
        Query(2 * nod + 1, m + 1, dr);
}

int main()
{
    f >> n >> q;
    for (i = 1; i <= n; ++i)
    {
        f >> x;
        poz = i;
        val = x;
        Update(1, 1, n);
    }
    for (i = 1; i <= q; ++i)
    {
        f >> x >> a >> b;
        if (x == 0)
        {
            maxi = 0;
            start = a;
            finish = b;
            Query(1, 1, n);
            g << maxi << '\n';
        }
        else
        {
            poz = a;
            val = b;
            Update(1, 1, n);
        }
    }
    return 0;
}