#include<fstream>
#define max(a,b) (a < b ? b : a)
#define nmax 100105
using namespace std;

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

int N, arbint[nmax], val , poz, M, maxi = -1;
int start, finish ; //pt interogari

void query(int nod, int st, int dr)
{
    if(start <= st && dr <= finish)
    {
        if(maxi < arbint[nod])
            maxi = arbint[nod];
            return;

    }
    int mij = (st + dr)/2;
    if(mij >= start)
       query(nod+ nod, st, mij);
    if(mij < finish)
        query(nod + nod + 1, mij + 1, dr);
}

void update(int nod, int st, int dr)
{
    if(st == dr)
    {
        arbint[nod] = val;
        return;
    }
    int mij = (st + dr) /2;
    if(mij >= poz)//actualizez doar in intervalele care il contin pe poz
        update(nod + nod, st, mij);
    else
        update(nod + nod + 1, mij + 1, dr);
    arbint[nod] = max(arbint[nod + nod] , arbint[nod + nod + 1]);//actualizez maximul intervalelor dupa ce am schimbat elementul de pe poz
}

void read()
{
    fin >>N >>M;
    for(int i = 1; i <= N;i++){

        fin>> val;  poz = i ;
        update(1, 1, N);
    }
    for(int i = 1; i <= M;i++)
    {
        int tip ;
        fin >> tip >>poz>> val;
        maxi = -1;
        if(tip == 1)
            update(1, 1, N);
        else
        {
            start = poz;
            finish = val;
            maxi = -1;
            query(1, 1, N);
            fout << maxi <<'\n';
        }
    }
}
int main()
{
    read();
    fin.close();
    return 0;

}