#include <iostream>
#include <fstream>
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int N, M, arbore[450000], r;
void adaug(int nod, int st, int dr, int x, int i) {
if (st == dr) {
arbore[nod] = x;
return;
}
int mijloc = (st + dr)/2;
if (i <= mijloc) adaug(2 * nod, st, mijloc, x, i);
else adaug(2 * nod + 1, mijloc + 1, dr, x, i);
arbore[nod] = max(arbore[2 * nod], arbore[2 * nod + 1] );
}
void query(int nod, int st, int dr, int a, int b)
{
if (a <= st && dr <= b)
{
if (r < arbore[nod]) r = arbore[nod];
return;
}
int mijloc = (st + dr)/2;
if (a <= mijloc) query(2 * nod, st, mijloc, a, b);
if (mijloc < b) query(2 * nod + 1, mijloc + 1, dr, a, b);
}
int main()
{
f >> N >> M;
for (int i = 1; i <= N; i++) {
int x;
f >> x;
adaug(1, 1, N, x, i);
}
for (int i = 1; i <= M; i++) {
int tip, a, b;
f >> tip >> a >> b;
if (tip == 1) adaug(1, 1, N, b, a);
else {
r = 0;
query(1, 1, N, a, b);
g << r << '\n';
}
}
return 0;
}