#include <fstream>
#include <assert.h>
using namespace std;

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

const int Dim  = 400068;



int n, m;
int maxArb[Dim];
int start, finish, Val, Pos, mx;


void Update(int nod, int left, int right);
void Query(int nod, int left, int right);

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


    fin >> n >> m;

    for ( int i = 1; i <= n; i++ )
    {
        fin >> x;
        Pos = i, Val = x;
        Update(1,1,n);
    }

    for ( int i = 1; i <= m; i++ )
    {
        fin >> x >> A >>B;
        if ( x== 0 )
        {
             mx = -1;
             start = A, finish = B;
             Query(1,1,n);

             fout << mx << '\n';
        }
        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] = max( maxArb[2*nod], maxArb[2*nod+1] );
}

void Query(int nod, int left, int right)
{
     if ( start <= left && right <= finish )
     {
          if ( mx < maxArb[nod] ) mx = 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);
}