#include <fstream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <cstring>
#include <climits>

using namespace std;

int n, m;

int arbore[400003], v[100003];

ifstream fin("arbint.in");
ofstream fout("arbint.out");

void build(int nod, int st, int dr)
{
    if (st == dr)
    {
        //e interval de lungime 1
        arbore[nod] = v[st];
        return;
    }

    int mij = (st + dr) / 2;
    //fac in stanga si in dreapta intervalul
    build(2 * nod, st, mij);
    build(2 * nod + 1, mij + 1, dr);

    arbore[nod] = max(arbore[2 * nod], arbore[2 * nod + 1]);
}

int query(int nod, int st, int dr, int qSt, int qDr)
{
    if (qSt <= st && dr <= qDr)
    {
        //intervalul meu e cuprins in intervalul mare
        return arbore[nod];
    }
    //verific sa imi formez intervalul din intervale mai mici
    int mij=(st+dr)/2;
    if(qDr<=mij)
    {
        //e in intervalul din stanga
        return query(2*nod,st,mij,qSt,qDr);
    }
    if(mij+1<=qSt)
    {
        return query(2*nod+1,mij+1,dr,qSt,qDr);
    }
    return max(query(2*nod,st,mij,qSt,qDr),query(2*nod+1,mij+1,dr,qSt,qDr));
}

void update(int nod, int st, int dr, int poz, int val)
{
    if (st == dr)
    {
        //e intervalul de lungime 1 de pe pozitia poz
        arbore[nod] = val;
        return;
    }
    int mij = (st + dr) / 2;
    if (poz <= mij)
    {
        //am pozitia in intervalul din stanga
        update(2 * nod, st, mij, poz, val);
    }
    else
    {
        //sunt in intervalul din dreapta
       update(2 * nod + 1, mij + 1, dr, poz, val);
    }
   
    
    //setez maximul
    arbore[nod] = max(arbore[2 * nod], arbore[2 * nod + 1]);
}

int main()

{

    fin >> n >> m;
    for (int i = 1; i <= n; i++)
    {
        fin >> v[i];
    }
    build(1, 1, n);

    for (int i = 1; i <= m; i++)
    {
        int cer;
        fin >> cer;
        if (cer == 0)
        {
            //am query
            int st, dr;
            fin >> st >> dr;
            fout << query(1, 1, n, st, dr)<<"\n";
        }
        else
        {
            int poz, val;
            fin >> poz >> val;
            update(1, 1, n, poz, val);
        }
    }
    return 0;
}