#include<iostream>
#include<fstream>
#define dim 100001
using namespace std;

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

inline int max(int a, int b) {
	if (a < b)
		return b;
	return a;
}

void update(int nod, int left, int right, int *arr, int pos, int val) {
	if (left == right) {
		arr[nod] = val;
		return;
	}

	int mid = (left + right) / 2;
	if (pos <= mid) update(nod * 2, left, mid, arr, pos, val);
	else update(nod * 2 + 1, mid + 1, right, arr, pos, val);

	arr[nod] = max(arr[2 * nod], arr[2 * nod + 1]);
}

void query(int nod, int left, int right, int *arr, int a, int b, int &maxim) {
	if (a <= left && right <= b) {
		if (maxim < arr[nod])
			maxim = arr[nod];
		return;
	}
		
	int mid = (left + right) / 2;
	if (a <= mid) query(2 * nod, left, mid, arr, a, b, maxim);
	if (mid < b) query(2 * nod + 1, mid + 1, right, arr, a, b, maxim);
}

int main() {
	int N, M, pos, val, X;
	int *arr = new int[5 * dim];
	f >> N >> M;
	for (int i = 1; i <= N; i++) {
		//propagam valorile la baza arborelui si alegem maximul de jos in sus pana la radacina
		f >> X;
		update(1, 1, N, arr, i, X);
	}

	for (int i = 1; i <= M; i++) {
		f >> X;
		if (X == 1) {
			f >> pos >> val;
			update(1, 1, N, arr, pos, val);
		}
		else {
			int a, b;
			f >> a >> b;
			int maxim = -1;
			query(1, 1, N, arr, a, b, maxim);
			g << maxim << endl;
		}
	}
	/*for (int i = 1; i <= 4 * N; i++)
		cout << arr[i] << " ";*/
	//system("Pause");
	return 0;
}