/* Vlad Voicu 2012 */
/* This program is free software. It comes without any warranty, to
 * the extent permitted by applicable law. You can redistribute it
 * and/or modify it under the terms of the Do What The Fuck You Want
 * To Public License, Version 2, as published by Sam Hocevar. See
 * http://sam.zoy.org/wtfpl/COPYING for more details. */

#include <cstdio>
#include <string>
#include <iostream>

int val, poz, max, start, end;
int v[450000];

int maxim(int a, int b) {
	if (a > b) {
		return a;
	}
	return b;
}
	

void Update(int nod, int left, int right) {
	if (left == right) {
		v[nod] = val;
		return;
	}
	int div = left + (right - left) / 2;
	if (poz <= div) {
		Update(nod*2, left, div);
	} else {
		Update(nod*2+1, div+1, right);
	}
  v[nod] = maxim(v[nod*2], v[nod*2+1]);
}	

void Query(int nod, int left, int right) {
	if (start <= left && right <= end) {
		if (max < v[nod])
			max = v[nod];
		return;
	}
	int div = left + (right - left) / 2;
	if (start <= div) Query(2*nod, left, div);
	if (div < end) Query(2*nod+1, div+1, right);
}

int main() {
  freopen("arbint.in", "r", stdin);
  freopen("arbint.out", "w", stdout);
	int n, m, i;
	scanf("%d%d", &n, &m);
	for (i = 0; i < n; i++) {
		poz = i + 1;
		scanf("%d", &val);
		Update(1, 1, n);
	}
	for (i = 0; i < m; i++) {
		int op;
		scanf("%d", &op);
		if (op == 0) {
			max = -1;
			scanf("%d%d", &start, &end);
			Query(1, 1, n); 
			printf("%d\n", max);
		} else {
			scanf("%d%d", &poz, &val);
			Update(1, 1, n);
		}
	}
	return 0;
}