#include <bits/stdc++.h>
using namespace std;
string np = "arbint";
ifstream f(np + ".in");
ofstream g(np + ".out");

// #define f cin
// #define g cout

struct segtree
{
    int size = 1;
    vector<int> val;

    void init(int n)
    {
        while (size < n)
            size *= 2;
        val.resize(size * 2);
    }

    void build(vector<int> &aux, int nod, int stnod, int drnod)
    {
        if (drnod - stnod == 1)
        {
            if (stnod < (int)aux.size())
                val[nod] = aux[stnod];
            return;
        }
        int mid = (stnod + drnod) / 2;
        build(aux, nod * 2 + 1, stnod, mid);
        build(aux, nod * 2 + 2, mid, drnod);
        val[nod] = max(val[nod * 2 + 1], val[nod * 2 + 2]);
    }
    void build(vector<int> &aux)
    {
        build(aux, 0, 0, size);
    }

    void set(int poz, int valoare, int nod, int stnod, int drnod)
    {
        if (drnod - stnod == 1)
        {
            val[nod] = valoare;
            return;
        }
        int mid = (stnod + drnod) / 2;
        if (poz < mid)
            set(poz, valoare, nod * 2 + 1, stnod, mid);
        else
            set(poz, valoare, nod * 2 + 2, mid, drnod);
        val[nod] = max(val[nod * 2 + 1], val[nod * 2 + 2]);
    }
    void set(int poz, int valoare)
    {
        set(poz, valoare, 0, 0, size);
    }

    int maxim(int st, int dr, int nod, int stnod, int drnod)
    {
        if (stnod >= dr or drnod <= st)
            return 0;
        if (stnod >= st and drnod <= dr)
            return val[nod];
        int mid = (stnod + drnod) / 2;
        int maxim1 = maxim(st, dr, nod * 2 + 1, stnod, mid);
        int maxim2 = maxim(st, dr, nod * 2 + 2, mid, drnod);
        return max(maxim1, maxim2);
    }
    int maxim(int st, int dr)
    {
        return maxim(st, dr, 0, 0, size);
    }

} mst;

int main()
{
    ios_base::sync_with_stdio(false);
    f.tie(nullptr);

    int n, m;
    f >> n >> m;
    mst.init(n);

    vector<int> aux(n);
    for (int i = 0; i < n; i++)
        f >> aux[i];
    mst.build(aux);

    for (int cer; f >> cer;)
        if (cer == 0)
        {
            int st, dr;
            f >> st >> dr;
            g << mst.maxim(st - 1, dr) << '\n';
        }
        else
        {
            int poz, val;
            f >> poz >> val;
            mst.set(poz - 1, val);
        }

    return 0;
}