#include <iostream>
#include <fstream>
using namespace std;
ifstream in("arbint.in");
ofstream out("arbint.out");
const int nMax = 100005;
int v[nMax];
int arb[4 * nMax];
void Build(int nod, int st, int dr)
{
    if(st == dr)
    {
        arb[nod] = v[st];
        return;
    }
    int mid = (st + dr) / 2;
    Build(nod * 2, st, mid);
    Build(nod * 2 + 1, mid + 1, dr);
    arb[nod] = max(arb[nod * 2], arb[nod * 2 + 1]);
}
/// face update pe pozitia poz cu valoarea val
void Update(int nod, int st, int dr, int poz, int val)
{
    if(st == dr)
    {
        arb[nod] = val;
        return;
    }
    int mid = (st + dr) / 2;
    if(poz <= mid)
        Update(nod * 2, st, mid, poz, val);
    else
        Update(nod * 2 + 1, mid + 1, dr, poz, val);
    arb[nod] = max(arb[nod * 2], arb[nod * 2 + 1]);
}

int Query(int nod, int st, int dr, int qx, int qy)
{
    if(qx <= st && dr <= qy)
        return arb[nod];
    int mij = (st + dr) / 2;
    int solst = 0, soldr = 0;
    if(qx <= mij)
        solst = Query(nod * 2,st, mij, qx, qy);
    if(mij + 1 <= qy)
        soldr = Query(nod * 2 + 1, mij + 1, dr, qx, qy);
    return max(solst, soldr);
}
int main()
{
    int n, m;
    in >> n >> m;
    for(int i = 1; i <= n; i ++)
        in >> v[i];
    Build(1, 1, n);
    for(int i = 1; i <= m; i ++)
    {
        bool op;
        in >> op;
        if(op == 0)
        {
            int st, dr;
            in >> st >> dr;
            int sol = Query(1, 1, n, st, dr);
            out << sol << "\n";
        }
        else
        {
            int poz, valoare;
            in >> poz >> valoare;
            Update(1, 1, n, poz, valoare);
        }
    }
    return 0;
}