#include <iostream>
#include <fstream>
#define nmax 100005
using namespace std;

int n, m, sol, op, a, b, v[nmax], H[4*nmax];

void update(int node, int lo, int hi, int pos, int val) {
	if(lo == hi) { H[node] = val; return; }
	int mid = (lo + hi) >> 1;
	if(pos <= mid) update(2*node, lo, mid, pos, val);
	else update(2*node+1, mid+1, hi, pos, val);
	H[node] = max(H[2*node], H[2*node+1]);
}

void query(int node, int lo, int hi, int a, int b) {
	if(a <= lo && hi <= b) { sol = max(sol, H[node]); return; }
	int mid = (lo + hi) >> 1;
	if(a <= mid) query(2*node, lo, mid, a, b);
	if(mid < b)  query(2*node+1, mid+1, hi, a, b);
}

void build(int node, int lo, int hi) {
	if(lo == hi) { H[node] = v[lo]; return; }
	int mid = (lo + hi) >> 1;
	build(2*node, lo, mid);
	build(2*node+1, mid+1, hi);
	H[node] = max(H[2*node], H[2*node+1]);
}

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

	f>>n>>m;
	for(int i=1; i<=n; i++) f>>v[i];
	build(1, 1, n);

	while(m--) {
		f>>op>>a>>b;
		if(op == 0) {
			sol = 0;
			query(1, 1, n, a, b);
			g<<sol<<"\n";
		}
		else update(1, 1, n, a, b);
	}

	return 0;
}