#include <fstream>
#include <limits.h>
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
int n,A[400010],v[100010],sol,m,i,a,b,t;
void build(int nod,int st,int dr) {
	if (st==dr)
		A[nod]=v[st]; //sau v[dr]
	else {
		int mid=(st+dr)/2;
		build(2*nod,st,mid);
		build(2*nod+1,mid+1,dr);
		A[nod]=max(A[2*nod],A[2*nod+1]);
	}
}
void update(int nod,int st,int dr,int p,int x) {
	if (st==dr) //si ==p
		A[nod]=x;
	else {
		int mid=(st+dr)/2;
		if (p<=mid)
			update(2*nod,st,mid,p,x);
		else
			update(2*nod+1,mid+1,dr,p,x);
		A[nod]=max(A[2*nod],A[2*nod+1]);
	}
}
void query(int nod,int st,int dr,int a,int b) {
	if (a<=st&&dr<=b)
		sol=max(sol,A[nod]);
	else {
		int mid=(st+dr)/2;
		if (a<=mid)
			query(2*nod,st,mid,a,b);
		if (b>mid)
			query(2*nod+1,mid+1,dr,a,b);
	}
}
int main() {
	fin>>n>>m;
	for (i=1;i<=n;i++)
		fin>>v[i];
	build(1,1,n);
	for (i=1;i<=m;i++) {
		fin>>t>>a>>b;
		if (t==0) {
			sol=0;
			query(1,1,n,a,b);
			fout<<sol<<"\n";
		}
		else
			update(1,1,n,a,b);

	}
	return 0;
}