#include <fstream>
#include <vector>

using namespace std;

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

class SegTree
{
    int n, *t;

    inline int my_max(const int a, const int b)
    {
        return ((a > b) ? a : b);
    }

    void init(const int node, const int a, const int b, const vector<int> &v)
    {
        if (a == b)
        {
            t[node] = v[(a - 1)];
            return;
        }

        int mid = ((a + b) >> 1);

        init((node << 1), a, mid, v);
        init(((node << 1) + 1), (mid + 1), b, v);

        t[node] = my_max(t[(node << 1)], t[((node << 1)) + 1]);

        return;
    }

    void update(const int node, const int a, const int b, const int pos, const int val)
    {
        if (a == b)
        {
            t[node] = val;
            return;
        }

        int mid = ((a + b) >> 1);

        if (pos <= mid)
            update((node << 1), a, mid, pos, val);
        else
            update(((node << 1) + 1), (mid + 1), b, pos, val);

        t[node] = my_max(t[(node << 1)], t[((node << 1) + 1)]);

        return;
    }

    int query(const int node, const int a, const int b, const int qa, const int qb)
    {
        if (qa > qb)
            return 0;
        if (a > b)
            return 0;

        if ((qa <= a) && (b <= qb)) // stop condition
            return t[node];

        int mid = ((a + b) >> 1);
        int p_left = (-1), p_right = (-1);

        if (qa <= mid)
            p_left = query((node << 1), a, mid, qa, qb);
        if (qb > mid)
            p_right = query(((node << 1) + 1), (mid + 1), b, qa, qb);

        return my_max(p_left, p_right);
    }

public:
    SegTree(const int size, const vector<int> &a)
    {
        n = size,
        t = new int[((n << 2) + 4)];

        init(1, 1, n, a);
    }

    ~SegTree()
    {
        delete t;
    }

    void update(const int pos, const int val)
    {
        update(1, 1, n, pos, val);
        return;
    }

    int query(const int left, const int right)
    {
        return query(1, 1, n, left, right);
    }
};

int main()
{
    int n = 0, m = 0;
    f >> n >> m;

    vector<int> a(n);
    for (int i = 0; i < n; ++i)
        f >> a[i];

    SegTree tree(n, a);

    for (int q = 1; q <= m; ++q)
    {
        short int type = 0;
        f >> type;

        int a = 0, b = 0;
        f >> a >> b;

        if (type == 1)
        {
            tree.update(a, b);
            continue;
        }

        g << tree.query(a, b) << '\n';
    }

    return 0;
}