#include <algorithm>
#include <iostream>
#include <fstream>
#include <cmath>
using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

#define nmax 100001
#define bucket_dim 320

int i, j, N, M;
int vmax, t1, t2;
int op, a, b, st, dr;
int v[nmax];

int cnt, pos_a, pos_b, dim, buckets;
int bucket[bucket_dim];
int I[bucket_dim];

int main() {
	fin >> N >> M;
	dim = sqrt(1.0 * N);
	I[0] = 1;
	for (i = 1; i <= N; ++i, ++j) {
		fin >> v[i];
		if (j == dim) {
			++cnt, j = 0;
			I[cnt] = i;
		}
		bucket[cnt] = max(bucket[cnt], v[i]);
	}
	for (i = 1; i <= M; ++i) {
		fin >> op >> a >> b;
		if (op) {
			--a;
			v[a + 1] = b;
			cnt = a / dim;
			if (bucket[cnt] <= b) bucket[cnt] = b;
		}
		else {
			--a;
			--b;
			vmax = 0;
			t1 = a / dim;
			t2 = b / dim;
			pos_a = a % dim;
			pos_b = b % dim;
			if (t1 != t2) {
				for (j = a + 1, cnt = pos_a; cnt <= dim; ++cnt, ++j) vmax = max(vmax, v[j]);
				for (j = b + 1, cnt = pos_b; cnt >= 0; --cnt, --j)  vmax = max(vmax, v[j]);
				++t1;
				--t2;
				for (; t1 <= t2; ++t1)
					vmax = max(vmax, bucket[t1]);
			}
			else {
				for (j = a + 1, cnt = pos_a; cnt <= pos_b; ++cnt, ++j)
					vmax = max(vmax, v[j]);
			}
			fout << vmax << '\n';
		}
	}
	return 0;
}