#include <fstream>
#include <vector>
#include <algorithm>

using namespace std;

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

void Update (int poz, int val, int nod, int st, int dr, vector<int>&MaxArb)
{
    if (st == dr)
    {
        MaxArb[nod] = val;
        return;
    }

    int mij = (st + dr) / 2;
    if (poz <= mij)
        Update(poz, val, nod * 2, st, mij, MaxArb);
    else
        Update(poz, val, nod * 2 + 1, mij + 1, dr, MaxArb);

    MaxArb[nod] = max(MaxArb[nod * 2], MaxArb[nod * 2 + 1]);
}

void Query (int&maxim, int Start, int Final, int nod, int st, int dr, vector<int>&MaxArb)
{
    if (st >= Start && dr <= Final)
    {
        maxim = max(maxim, MaxArb[nod]);
        return;
    }

    int mij = (st + dr) / 2;
    if (mij >= Start) Query(maxim, Start, Final, nod * 2, st, mij, MaxArb);
    if (mij < Final)  Query(maxim, Start, Final, nod * 2 + 1, mij + 1, dr, MaxArb);
}

int main()
{
    int n, T;
    in >> n >> T;

    vector<int> MaxArb(n * 4);

    for (int i = 1; i <= n; i++)
    {
        int x;
        in >> x;
        Update(i, x, 1, 1, n, MaxArb);
    }

    while (T--)
    {
        int tip, a, b;

        in >> tip >> a >> b;

        if (tip == 1)
        {
            Update(a, b, 1, 1, n, MaxArb);
            continue;
        }

        int maxim = 0;
        Query(maxim, a, b, 1, 1, n, MaxArb);
        out << maxim << '\n';
    }

    return 0;
}