#include <fstream>
using namespace std;
ifstream fi("arbint.in");
ofstream fo("arbint.out");
#define dim 100001

int N, M;
int MaxArb[4*dim];
int A,B, 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 ( A <= left && right <= B )
     {    if ( maxim < MaxArb[nod] ) maxim = MaxArb[nod];
          return;
     }
int div = (left+right)/2;
if ( A <= div ) Query(2*nod,left,div);
if ( div < B) Query(2*nod+1,div+1,right);
}


int main()
{
    int X;

    fi>>N>>M;
    for ( int i = 1; i <= N; i++ )
    {
        fi>>X;
        Pos = i, Val = X;
        Update(1,1,N);
    }

    for ( int i = 1; i <= M; i++ )
    {
        fi>>X>>A>>B;
        if ( X == 0 )
        {
             maxim = -1;
             Query(1,1,N);
             fo<<maxim<<'\n';
        }
        else
        {
            Pos = A, Val = B;
            Update(1,1,N);
        }
    }
}