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

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

const int maxn = 1e5 + 5;
int V[maxn], Aint[maxn << 2], maxx;

inline int max(const int &a, const int &b) {
	return a > b ? a : b;
}

void Build(int node, int left, int right) {
	if (left == right) {
		Aint[node] = V[left];
		return;
	}
	int mid = left + ((right - left) >> 1);
	Build(node << 1, left, mid);
	Build(node << 1 | 1, mid + 1, right);
	Aint[node] = max(Aint[node << 1], Aint[node << 1 | 1]);
}

void Update(int node, int left, int right, int pos, int val) {
	if (left == right) {
		Aint[node] = val;
		return;
	}
	int mid = left + ((right - left) >> 1);
	if (pos <= mid) {
		Update(node << 1, left, mid, pos, val);
	}
	else {
		Update(node << 1 | 1, mid + 1, right, pos, val);
	}
	Aint[node] = max(Aint[node << 1], Aint[node << 1 | 1]);
}

void Query(int node, int left, int right, int inc, int sf) {
	if (inc <= left && right <= sf) {
		maxx = max(maxx, Aint[node]);
		return;
	}
	int mid = left + ((right - left) >> 1);
	if (inc <= mid) {
		Query(node << 1, left, mid, inc, sf);
	}
	if (sf > mid) {
		Query(node << 1 | 1, mid + 1, right, inc, sf);
	}
}

int main() {
	ios_base::sync_with_stdio(false);
	int n, m, x, y, op, i;
	fin >> n >> m;
	for (i = 1; i <= n; i++) {
		fin >> V[i];
	}
	Build(1, 1, n);
	for (i = 1; i <= m; i++) {
		fin >> op >> x >> y;
		if (op == 0) {
			maxx = -1;
			Query(1, 1, n, x, y);
			fout << maxx << "\n";
		}
		else {
			Update(1, 1, n, x, y);
		}
	}
	fin.close();
	fout.close();
	return 0;
}