#include <fstream>
#include <iostream>
#include <complex>
#include <iomanip>
#include <string>
#include <set>
#include <vector>
#include <map>
#include <queue>
#include <stack>
#include <list>
#include <algorithm>
#include <cmath>
#include <ctime>
#include <cassert>
#include <cstdio>
#include <cstdlib>

using namespace std;

//```
#define ONLINE_JUDGE

const double epsilon = 1e-7;
#define LL long long
#define ULL unsigned long long 
#define MOD1 666013
#define MOD2 666019
#define base 73

typedef stack<int> si;
typedef vector<int> vi;
typedef vector<long long> vl;
typedef vector<bool> vb;
typedef vector<vi> vvi;
typedef vector<vl> vvl;
typedef vector<double> vd;
typedef vector<string> vs;
typedef pair<int, int> ii;
typedef pair<long long, long long> ll;
typedef vector<ii> vii;
typedef vector<ll> vll;

#define all(V) V.begin(), V.end()
#define allr(V) V.rbegin(), V.rend()
#define for_c_it(container, it) for (auto it : container)
#define present(container, element) (container.find(element) != container.end()) 
#define sz(a) int((a).size()) 
#define pb push_back 
#define mp make_pair
#define zeroes(x) ((x ^ (x - 1)) & x)

si stk;
vi arb;
int N, M, ans, pos, val, a, b;

void add(int node, int lf, int rg);
void get(int node, int lf, int rg);

int main() {
#ifndef ONLINE_JUDGE
	freopen("input.txt", "r", stdin);
#else 
	freopen("arbint.in", "r", stdin);
	freopen("arbint.out", "w", stdout);
#endif
	int i, x, c;
	scanf("%d %d", &N, &M);
	arb.resize(N * 4);
	for (i = 1; i <= N; ++i) {
		scanf("%d", &x);
		pos = i;
		val = x;
		add(1, 1, N);
	}
	for (i = 1; i <= M; ++i) {
		scanf("%d %d %d", &c, &a, &b);
		if (c == 0) {
			ans = -1;
			get(1, 1, N);
			printf("%d\n", ans);
		}
		else {
			pos = a;
			val = b;
			add(1, 1, N);
		}
	}

	return 0;
}

void add(int node, int lf, int rg) {
	if (lf == rg) {
		arb[node] = val;
	}
	else {
		int mid = (lf + rg) / 2;
		if (pos <= mid) {
			add(node * 2, lf, mid);
		}	
		else {
			add(node * 2 + 1, mid + 1, rg);
		}
		arb[node] = max(arb[node * 2], arb[node * 2 + 1]);
	}
}

void get(int node, int lf, int rg) {
	if (a <= lf && rg <= b) {
		ans = max(ans, arb[node]);
	}
	else {
		int mid = (lf + rg) / 2;
		if (a <= mid) {
			get(node * 2, lf, mid);
		}	
		if (mid < b){
			get(node * 2 + 1, mid + 1, rg);
		}
	}
}