#include <fstream>
#include <iostream>
#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 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);

}

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] );
     Query(1,1,N);

     printf("%d\n", maxim);


}

 
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);
      Query(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);
      }
}
}