#include <fstream>
#include <algorithm>
#define NMAX 100005

using namespace std;

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

int i, n, v[4 * NMAX], a, b, nrquiz, type, ans, pos, value, lleft, rright;

void Update(int node, int left, int right)
{
    if (left == right)
    {
        v[node] = value;
        return;
    }

    int mid = (left + right) / 2;

    if (pos <= mid)
        Update(2 * node, left, mid);
    else
        Update(2 * node + 1, mid + 1, right);

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

void Query(int node, int left, int right)
{
    if (lleft <= left && rright >= right)
    {
        if (v[node] > ans)
            ans = v[node];
        return;
    }

    int mid = (left + right) / 2;

    if (lleft <= mid)
        Query(2 * node, left, mid);

    if (rright > mid)
        Query(2 * node + 1, mid + 1, right);
}

int main()
{
    f >> n >> nrquiz;

    for (i = 1; i <= n; ++ i)
    {
        f >> value;
        pos = i;
        Update(1, 1, n);
    }

    while (nrquiz)
    {
        nrquiz --;

        f >> type >> a >> b;

        if (type == 1)
        {
            pos = a;
            value = b;
            Update(1, 1, n);
        }
        else
        {
            ans = -1;
            lleft = a;
            rright = b;
            Query(1, 1, n);
            g << ans << '\n';
        }
    }
    return 0;
}