#include <stdio.h> 
#include <fstream> 
#include <assert.h>   
using namespace std; 
#define in "arbint.in" 
#define out "arbint.out" 
#define dim 100001 
int N, M; 
int MaxArb[4*dim+66]; 
int start, finish, Val, Pos, maxim; 
	
	inline int Maxim(int a, int b) {      
if ( a > b ) return a; 
return b; 
} 
void Update(int,int,int); 
void Query(int,int,int); 
	
	int main() 
{     
int X, A, B;     
freopen(in,"r",stdin);     
freopen(out,"w",stdout);   
scanf("%d%d", &N, &M);   
for ( int i = 1; i <= N; i++ )    
{         
scanf("%d", &X);        
Pos = i, Val = X;         
Update(1,1,N);    
}        
for ( int i = 1; i <= M; i++ )     
{        
scanf("%d%d%d", &X, &A, &B);         
if ( X == 0 )        
{              
maxim = -1;             
start = A, finish = B;             
Query(1,1,N);              
printf("%d\n", maxim);       
}        
else        
{           
Pos = A, Val = B;            
Update(1,1,N);       
}     
} 
} 

	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] = Maxim( 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); 
}