#include <stdio.h>
 
int N, M;
int aint[400001];
int start, finish, Val, Pos, maxim;
 
inline int Maxim(int a, int b) {
       if ( a > b ) return a;
       return b;
}
 
void Update(int nod, int left, int right)
{
     if ( left == right )
     {
          aint[nod] = Val;
          return;
     }
 
     int div = (left+right)/2;
     if ( Pos <= div ) Update(2*nod,left,div);
     else              Update(2*nod+1,div+1,right);
 
     aint[nod] = Maxim( aint[2*nod], aint[2*nod+1] );
}
 
void Query(int nod, int left, int right)
{
     if ( start <= left && right <= finish )
     {
          if ( maxim < aint[nod] ) maxim = aint[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;
    FILE *fin = fopen("arbint.in", "r");
    FILE *fout = fopen("arbint.out", "w");
 
    fscanf(fin,"%d%d", &N, &M);
    for ( int i = 1; i <= N; i++ )
    {
        fscanf(fin,"%d", &X);
        Pos = i, Val = X;
        Update(1,1,N);
    }
 
    for ( int i = 1; i <= M; i++ )
    {
        fscanf(fin,"%d%d%d", &X, &A, &B);
        if ( X == 0 )
        {
             maxim = -1;
             start = A, finish = B;
             Query(1,1,N);
 
             fprintf(fout,"%d\n", maxim);
        }
        else
        {
            Pos = A, Val = B;
            Update(1,1,N);
        }
    }
    fclose(fin);
    fclose(fout);
}