#include <fstream>

#define max(a, b) (a > b) ? a : b

int tree[500000];

void update(int node, int l, int r, int a, int b);
int query(int node, int l, int r, int a, int b);

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

    int nV, nO, op, a, b;

    in >> nV >> nO;

    for(int i = 1; i <= nV; i++)
        in >> b, update(1, 1, nV, i, b);

    for(int i = 0; i < nO; i++)
    {
        in >> op >> a >> b;
        if(op) update(1, 1, nV, a, b);
        else out << query(1, 1, nV, a, b) << '\n';
    }

    return 0;
}

void update(int node, int l, int r, int a, int b)
{
    if(l == r)
    {
        tree[node] = b;
        return;
    }
    int m = (l + r) / 2;
    if(a <= m)
        update(2 * node, l, m, a, b);
    else
        update(2 * node + 1, m + 1, r, a, b);
    tree[node] = max(tree[2 * node], tree[2 * node + 1]);
}

int query(int node, int l, int r, int a, int b)
{
    if(a <= l && r <= b)
        return tree[node];
    int max1 = -1, max2 = -1, m = (l + r) / 2;
    if(a <= m) max1 = query(node * 2, l, m, a, b);
    if(b >= m) max2 = query(node * 2 + 1, m + 1, r, a, b);
    return max(max1, max2);
}