#include <fstream>

using namespace std;

ifstream cin ("arbint.in");
ofstream cout ("arbint.out");

const int MAX = static_cast<const int>(1e5 + 14);

int v [MAX];
int tree [MAX << 2];

void build (int node, int st, int dr)
{
    if (st == dr)
    {
        tree[node] = v[st];
        return;
    }

    int mij = (st + dr) / 2;

    build(node * 2, st, mij);
    build(node * 2 + 1, mij + 1, dr);

    tree[node] = max(tree[node * 2], tree[node * 2 + 1]);
}

void update (int node, int st, int dr, const int pos, const int val)
{
    if (st == dr)
    {
        tree[node] = val;
        return;
    }

    int mij = (st + dr) / 2;
    if (pos <= mij)
        update(node * 2, st, mij, pos, val);
    else update(node * 2 + 1, mij + 1, dr, pos, val);

    tree[node] = max(tree[node * 2], tree[node * 2 + 1]);
}

int query (int node, int st, int dr, const int a, const int b)
{
    if (a <= st and dr <= b)
        return tree[node];

    int mij = (st + dr) / 2;

    int answer = 0;
    if (a <= mij)
        answer = max(answer, query(node * 2, st, mij, a, b));
    if (b > mij)
        answer = max(answer, query(node * 2 + 1, mij + 1, dr, a, b));

    return answer;
}

int main() {
    int n, m;
    cin >> n >> m;
    for (int i = 1; i <= n; ++ i)
        cin >> v [i];
    build(1, 1, n);

    while (m --)
    {
        int tip;
        cin >> tip;
        if (!tip)
        {
            int a, b;
            cin >> a >> b;
            cout << query(1, 1, n, a, b) << '\n';
        }
        else
        {
            int pos, val;
            cin >> pos >> val;
            update(1, 1, n, pos, val);
        }
    }
    return 0;
}