#include<fstream> 
#include<algorithm>
#define DIM 100001

using namespace std; 

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

int MaxArb[4*DIM+66], pos, val, N, M, sol, Start, Finish; 

void Update(int nod, int left, int right) 
{
	if(left == right) 
	{
		MaxArb[nod] = val; 
		return; 
	}
	else {
	int div = (left + right)/2; 
	if(pos <= div)    Update(2*nod, left, div); 
	else              Update(2*nod+1, div+1, right); 
	
	MaxArb[nod] = max(MaxArb[2*nod], MaxArb[2*nod+1]); 
	}
}
void Query(int nod, int left, int right) 
{
	if(Start <= left && right <= Finish) 
	{
		sol = max(sol, MaxArb[nod]); 
		return; 
	}
	else {
    int div = (left + right)/2;
	if(Start <= div)         Query(2*nod, left, div); 
	else if(div < Finish)    Query(2*nod+1, div+1, right);
	}	
}
int main() 
{
	int i, nr, cod, A, B;
	
	in >> N >> M; 
	
	for(i = 1; i <= N; i++) 
	{
		in >> nr; 
		pos = i; val = nr; 
		Update(1, 1, N);
	}
	
	for(i = 1; i <= M; i++) 
	{
		in >> cod >> A >> B; 
		if(cod == 0) 
		{
			Start = A; 
			Finish = B; 
			sol = -1;
			Query(1, 1, N);
			out << sol << '\n'; 
		}
		else
		{
			pos = A; 
			val = B; 
			Update(1, 1, N); 
		}
	}
	
	return 0; 
}