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

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

#define dim 600001

int N,M; 
int MaxArb[dim];
int start, finish, Val, Pos, maxim; 

void Update(int nod, int left, int right) 
{
	if( left == right ) 
	{
		MaxArb[nod] = Val; 
		return; 
	}
	
	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 ) 
	{
		if( maxim < MaxArb[nod] ) 
			maxim = MaxArb[nod];
		return; 
	}
	
    int div = (left + right)/2;
	if( start <= div )    Query(2*nod,left,div); 
	if( div < finish )    Query(2*nod+1,div+1,right);   
			
}

int main() 
{
	int X, A, B; 

	in >> N >> M; 
	
	for(int i = 1; i <= N; i++) 
	{
		in >> X;
		Pos = i, Val = X;
		Update(1,1,N);
	}
	
	for(int i = 1; i <= M; i++) 
	{
		in >> X >> A >> B; 
		if( X == 0 ) 
		{
            maxim = -1;
            start = A, finish = B;			
			Query(1,1,N); 
			out << maxim;
		}
		else 
		{
			Pos = A, Val = B;
            Update(1,1,N);
		}
	}
}