#include <fstream>
#include <iostream>
#include <cmath>
using namespace std;

int query(int index, const int &left, const int &right, int cLeft, int cRight, int tree[])
{
    if (left <= cLeft && right >= cRight)
        return tree[index];

    if (cLeft > right || cRight < left)
        return -1;

    int leftMax = query(index * 2 + 1, left, right, cLeft, (cLeft + cRight) / 2, tree);
    int rightMax = query(index * 2 + 2, left, right, (cLeft + cRight) / 2 + 1, cRight, tree);

    return max(leftMax, rightMax);
}

void update(int index, const int& pos, int left, int right, int a[], int tree[])
{
    if (left == right && pos == left)
        tree[index] = a[pos];
    else if (pos >= left && pos <= right)
    {
        update(index * 2 + 1, pos, left, (left + right) / 2, a, tree);
        update(index * 2 + 2, pos, (left + right) / 2 + 1, right, a, tree);

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

int main()
{
    int N, M, i, length;
    ifstream f("arbint.in");
    f >> N >> M;
    length = (1 << ((int)log2(N) + 2)) - 1;
    int a[N], tree[length];
    fill(tree, tree + length, -1);
    for (i = 0; i < N; i++)
    {
        f >> a[i];
        update(0, i, 0, N - 1, a, tree);
    }

    int op, x, y;
    ofstream g("arbint.out");
    for (i = 0; i < M; i++)
    {
        f >> op >> x >> y;
        if (op == 0)
            g << query(0, x - 1, y - 1, 0, N - 1, tree) << '\n';
        else if (op == 1)
        {
            a[x - 1] = y;
            update(0, x - 1, 0, N - 1, a, tree);
        }
    }
    f.close();
    g.close();

    return 0;
}