#include <fstream>
#include <cstdio>
using namespace std;

const int MAXN = 131072;//cica lica putere 2 mai rapid, dar merge si cu MAXN

int arbore[2 * MAXN];
int n;

int localizare_frunza(int p, int a, int b, int f)
{
    int mij = (a + b) / 2;
    if (a == b)
        return p;
    if (f <= mij)
        return localizare_frunza(2 * p, a, mij, f);
    else return localizare_frunza(2 * p + 1, mij + 1, b, f);
}

void actualizare_recursiva(int p)
{
    arbore[p] = max(arbore[2 * p], arbore[2 * p + 1]);
    if (p == 1)
        return;
    actualizare_recursiva(p / 2);
}

void actualizare_arbore(int f, int val)
{
    int pf = localizare_frunza(1,1,n,f);
    arbore[pf] = val;
    actualizare_recursiva(pf / 2);
}

int interogare_recursiva(int p, int a, int b, int s, int d)
{
    if (s <= a && b <= d)
        return arbore[p];
    if (b < s || d < a)
        return -1;
    int mij = (a + b) / 2;
    return max(interogare_recursiva(2 * p, a, mij, s, d), interogare_recursiva(2 * p + 1, mij + 1, b, s, d));
}

inline int interogare_arbore(int s, int d)
{
    return interogare_recursiva(1, 1, n, s, d);
}

void citire()
{
    int nr;
    int m;
    int test,a,b;
    //ifstream in("arbint.in");
    //ofstream out("arbint.out");
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    //in >> n >> m;
    scanf("%d%d",&n,&m);
    for (int i = 1;i <= n;++i)
    {
        //in >> nr;
        scanf("%d",&nr);
        actualizare_arbore(i,nr);
    }
    for (int i = 1;i <= m;++i)
    {
        scanf("%d%d%d",&test,&a,&b);
        //in >> test >> a >> b;
        if (test == 0)
            //out << interogare_arbore(a,b) << '\n';
            printf("%d\n",interogare_arbore(a,b));
        else actualizare_arbore(a,b);
    }
}

int main()
{
    citire();
    return 0;
}