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

ifstream cin("arbint.in");
ofstream cout("arbint.out");

vector<int> aint;

int query(int nod,int st,int dr,int ql,int qr)
{
    if(ql <= st && qr >= dr)
        return aint[nod];

    if(ql > dr || qr < st)
        return 0;

    int mid = (st + dr) / 2;
    int stanga = query(nod * 2,st,mid,ql,qr);
    int dreapta = query(nod * 2 + 1,mid + 1,dr,ql,qr);

    return max(stanga,dreapta);
}

void update(int nod,int val,int n)
{
    aint[nod + n] = val;
    for(int tata = (nod + n) / 2; tata >= 1; tata /= 2)
        {
            aint[tata] = max(aint[tata * 2],aint[tata * 2 + 1]);
        }
}

int main()
{
    int n,q;
    cin >> n >> q;
    vector<int> a(n);

    for(int i = 0 ; i < n ; i++)
        {
            cin >> a[i];
        }

    while(__builtin_popcount(n) != 1)
        {
            a.push_back(0);
            n++;
        }

    aint.resize(n * 2);

    //build

    for(int i = 0 ; i < n ; i++)
        {
            aint[n + i] = a[i];
        }


    for(int i = n - 1; i >= 1 ; i--)
        {
            aint[i] = max(aint[i * 2],aint[i * 2 + 1]);
        }

    //query


    while(q--)
        {
            int t,l,r;
            cin >> t >> l >> r;

            if(t == 0)
                {
                    l--,r--;
                    int rez = query(1,0,n - 1,l,r);
                    cout << rez << '\n';
                }
            else
                {
                    update(l - 1,r,n);
                }
        }

    return 0;

}