#include <fstream>
#include <algorithm>
#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;

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] = std::max( 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);
}

int main()
{
    int x, a, b;
    std::ifstream  fin(in);
    std::fstream fout(out);
    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 )
        {
            maxim = -1;
            start = a, finish = b;
            Query(1,1,n);
            fout << maxim << "\n";
        }
        else
        {
            Pos = a, Val = b;
            Update(1,1,n);
        }
    }
    return 0;
}