#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define mp make_pair
#define dbg(x) cout << #x <<": " << x << "\n";
using ll = long long;

const string myf = "arbint";
ifstream fin(myf + ".in");
ofstream fout(myf + ".out");


///nrdiv = (e1 + 1) * (e2 + 1)....
///sumdiv =

int n, m;
int op, x, y;
int a[4 * 100001];

void build(int nod, int st, int dr) {
	if (st == dr) {
		fin >> a[nod];
		return;
	}
	int mid = (st + dr) >> 1;
	build(nod << 1 , st, mid);
	build(nod << 1 | 1, mid + 1, dr);
	a[nod] = max(a[nod << 1], a[nod << 1 | 1]);
}

void upd(int nod, int st, int dr, int poz, int val) {

	if (st == dr) {
		a[nod] = val;
		return;
	}
	int mid = (st + dr) >> 1;
	if (poz <=  mid)
		upd(nod << 1, st, mid, poz, val);
	else
		upd(nod << 1 | 1, mid + 1, dr, poz, val);
	a[nod] = max(a[nod << 1], a[nod << 1 | 1]);
}

int qry(int nod, int st, int dr, int x, int y) {
	if (st > dr || st > y || dr < x)
		return -1;
	if (st >= x && dr <= y)
		return a[nod];
	int mid = (st + dr) >> 1;
	int q1 = qry(nod << 1, st, mid, x, y);
	int q2 = qry(nod << 1 | 1, mid + 1, dr, x, y);
	return max(q1, q2);

}

int main() {

	fin >> n >> m;
	build(1, 1, n);

	while (m--) {
		fin >> op >> x >> y;
		if (op == 0)
			fout << qry(1, 1, n, x, y) << '\n';
		else upd(1, 1, n, x, y);
	}

	fin.close();
	fout.close();
	return 0;
}