#include <fstream>
#include <vector>

void build(const int a, const int b, const std::vector<int> &v, std::vector<int> &it, const int index = 0)
{
    if(a == b)
    {
        it[index] = v[a];
        return;
    }

    const int mid = (a + b) / 2;
    build(a, mid, v, it, 2*index + 1);
    build(mid + 1, b, v, it, 2*index + 2);

    it[index] = std::max(it[2*index + 1], it[2*index + 2]);
}

void update(const int pos, const int val, const int a, const int b, std::vector<int> &it, const int index = 0)
{
    if(a == b)
    {
        it[index] = val;
        return;
    }

    int mid = (a + b) / 2;
    if(pos <= mid)
        update(pos, val, a, mid, it, 2*index + 1);
    else
        update(pos, val, mid + 1, b, it, 2*index + 2);

    it[index] = std::max(it[2*index + 1], it[2*index + 2]);
}


int query(const int qA, const int qB, const int a, const int b, const std::vector<int> &it, const int index = 0)
{
    if(qA <= a && b <= qB)
        return it[index];

    const int mid = (a + b) / 2;
    if(qB <= mid)
        return query(qA, qB, a, mid, it, 2*index + 1);
    if(qA > mid)
        return query(qA, qB, mid + 1, b, it, 2*index + 2);

    return std::max(query(qA, qB, a, mid, it, 2*index + 1), query(qA, qB, mid + 1, b, it, 2*index + 2));
}

int main()
{
    std::ifstream in("arbint.in");
    std::ofstream out("arbint.out");

    int n, m; in >> n >> m;
    std::vector v(n, 0);
    for (int i = 0; i < n; ++i)
        in >> v[i];

    std::vector intervalTree(2*n - 1, 0);
    build(0, n - 1, v, intervalTree);

    for(int ii = 0; ii < m; ii++)
    {
        int t, a, b; in >> t >> a >> b;

        if(t == 1)
            update(a - 1, b, 0, n - 1, intervalTree);
        else
            out << query(a - 1, b - 1, 0, n - 1, intervalTree) << '\n';
    }

    in.close();
    out.close();
    return 0;
}