#include <fstream>

using namespace std;

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

int n, m;
int arb[(1 << 18)];

inline int maxim(int x, int y)
{
    return x > y ? x : y;
}

void actualizeaza(int nod, int st, int dr, int poz, int val)
{
    if(poz <= st && dr <= poz)
    {
        arb[nod] = val;
        return;
    }

    int mij = (st + dr) >> 1;
    if(poz <= mij)
        actualizeaza((nod << 1), st, mij, poz, val);
    if(mij + 1 <= poz)
        actualizeaza((nod << 1) + 1, mij + 1, dr, poz, val);
    arb[nod] = maxim(arb[2 * nod], arb[2 * nod + 1]);
}

int interogare(int nod, int st, int dr, int x, int y)
{
    if(x <= st && dr <= y)
        return arb[nod];

    int mij = (st + dr) >> 1;

    int rez = 0;
    if(x <= mij)
        rez = maxim(rez, interogare((nod << 1), st, mij, x, y));
    if(mij + 1 <= y)
        rez = maxim(rez, interogare((nod << 1) + 1, mij + 1, dr, x, y));

    return rez;
}

void citire()
{
    in >> n >> m;

    for(int i = 1; i <= n; i++)
    {
        int val;
        in >> val;
        actualizeaza(1, 1, n, i, val);
    }
}

int main()
{
    citire();

    for(int i = 1; i <= m; i++)
    {
        int tip, a, b;
        in >> tip >> a >> b;

        if(tip == 0)
            out << interogare(1, 1, n, a, b) << '\n';
        else
            actualizeaza(1, 1, n, a, b);
    }
    return 0;
}