#include <fstream>
#include <vector>
#include <bitset>
using namespace std;

const string fis = "arbint";
ifstream is(fis + ".in");
ofstream os(fis + ".out");

using VI = vector<int>;
using VS = vector<short>;
using VVI = vector<VI>;

int n, N, m;
int tip, a, b;
VI arb;

int sum(int nod, int st, int dr)
{
    if ( a <= st && dr <= b )
        return arb[nod];
    int md = ( st + dr ) / 2, s = 0;
    if ( a <= md )
        s = sum(2 * nod, st, md);
    if ( md < b )
        s = max(s, sum(2 * nod + 1, md + 1, dr));
    return s;
}

int main()
{
    is >> n >> m;
    for ( N = 1; N < n; N <<= 1 );
    arb = VI(2 * N);
    for ( int i = 0; i < n; ++i )
        is >> arb[N + i];
    for ( int i = N - 1; i; --i )
        arb[i] = max(arb[2 * i], arb[2 * i + 1]);
    while ( m-- )
    {
        is >> tip >> a >> b;
        if ( tip )
        {
            arb[N + a - 1] = b;
            for ( int i = ( N + a - 1 ) / 2; i; i /= 2 )
                arb[i] = max(arb[2 * i], arb[2 * i + 1]);
        }
        else
            os << sum(1, 1, N) << "\n";
    }
    is.close();
    os.close();
    return 0;
}