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

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

int v[100000], d[400000];

void creare(int nod, int st, int dr)
{
    if(st == dr)
    {
        d[nod] = v[st];
        return;
    }
    creare(nod * 2, st, (st + dr) / 2);
    creare(nod * 2 + 1, (st + dr) / 2 + 1, dr);
    d[nod] = max(d[nod * 2], d[nod * 2 + 1]);
}

void modificare(int nod, int st, int dr, int i, int val)
{
    if(i < st || i > dr)
        return;

    if(st == dr)
    {
        d[nod] = val;
        return;
    }
    modificare(nod * 2, st, (st + dr) / 2, i, val);
    modificare(nod * 2 + 1, (st + dr) / 2 + 1, dr, i, val);
    d[nod] = max(d[nod * 2], d[nod * 2 + 1]);
}

int maxim(int nod, int st, int dr, int i, int j)
{
    if(dr < i || st > j)
        return 0;

    if(i <= st && dr <= j)
        return d[nod];

    return max(maxim(nod * 2, st, (st + dr) / 2, i, j), maxim(nod * 2 + 1, (st + dr) / 2 + 1, dr, i, j));
}

int main()
{
int n, m, x, y, z;

fin >> n >> m;

for(int i = 1; i <= n; i++)
    fin >> v[i];

creare(1, 1, n);

for(int i = 0; i < m; i++)
{
    fin >> z >> x >> y;
    if(z)
        modificare(1, 1, n, x, y);
    else
        fout << maxim(1, 1, n, x, y) << "\n";
}

return 0;
}