#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>

typedef long long ll;

const ll mod=1e9+7;
const ll MAXN=1e7;
const ll minfinit=-1e7;
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};

#define all(x) x.begin(),x.end()
#define allr(x) x.rbegin(),x.rend()
#define rc(x)  return cout<<x<<"\n",0
#define sz(s)  (int) s.size()
#define pb push_back
#define mp make_pair
#define fr first
#define sc second

using namespace std;

ll t[4*MAXN],m,n;
void buildSegTree(int arr[], int v, int tl, int tr) {
	if (tl==tr) {
		t[v]=arr[tl];
	}
	else {
		int tm=(tl+tr)/2;
		buildSegTree(arr, 2*v,tl,tm);
		buildSegTree(arr,2*v+1,tm+1,tr);
		t[v]=max(t[v*2],t[v*2+1]);
	}
}
void changeValue(int a[], int v, int tl, int tr, int pos, int newVal) {
	if (tl==tr) {
		t[v]=newVal;
		a[tl]=pos;
	}
	else {
		int tm=(tl+tr)/2;
		if (pos<=tm) {
			changeValue(a,2*v,tl,tm,pos,newVal);
		}
		else {
			changeValue(a,2*v+1,tm+1,tr,pos,newVal);
		}
		t[v]=max(t[v*2],t[v*2+1]);
	}
}
int maxValue(int v, int tl, int tr, int l, int r) { 
	if (tr<l || tl>r) {
		return minfinit;
	}	
	else if (tl>=l && tr<=r) {
		return t[v];
	}
	else {
		ll tm=(tl+tr)/2;
		return max(maxValue(2*v,tl,tm,l,r),maxValue(2*v+1,tm+1,tr,l,r));
	}
	
}

int main() {
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	ifstream cin("arbint.in");
	ofstream cout("arbint.out");
	cin >> n >> m;
	int arr[n+5];
	for (int i=1; i<=n; i++) {
		cin >> arr[i];
	}
	buildSegTree(arr,1,1,n);
	while (m--) {
		int cas,a,b;
		cin >> cas;
		if (cas) {
			cin >> a >> b;
			changeValue(arr,1,1,n,a,b);
		}
		else {
			cin >> a >> b;
			cout << maxValue(1,1,n,a,b) << '\n';
		}
	}


}