#include <fstream>
using namespace std;

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

int n,m,start,finish,Arb[400000];
int i,x,pos,val,a,mij,b,maxim,tip;
void Update(int nod,int left,int right); //pos & val
void Query(int nod,int left,int right);


int main()
{
    fin>>n>>m;
    for(i=1;i<=n;++i)
    {
        fin>>x;
        pos=i;
        val =x;
        Update(1,1,n);
    }
    for(i=1;i<=m;++i)
    {
        fin>>tip>>a>>b;
        if(tip==0) //maximul dintre a si b
        {
            maxim=-1;
            start=a;
            finish=b;
            Query(1,1,n);
            fout<<maxim<<'\n';
        }
        else //valoarea elementului de pe pozitia a devine b
        {
            pos=a;
            val=b;
            Update(1,1,n);
        }
    }
    return 0;
}

void Update(int nod,int left,int right) //pos & val
{
    if(left==right)
    {
        Arb[nod]=val;
        return ;
    }
    int  mij=(left+right)/2;
    if(pos<=mij) Update(nod*2,left,mij);
    else         Update(nod*2+1,mij+1,right);

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

void Query(int nod,int left,int right) //start,finish,maxim
{
    if(left>=start&&right<=finish) // START[  left()right   ]FINISH //este un subinterval al intervalului pe care il cautam
    {
        if(Arb[nod]>maxim)
        maxim=Arb[nod];
        return ;
    }
    int mij=(left+right)/2;
    if(start<=mij) Query(nod*2,left,mij);
    if(mij<finish) Query(nod*2+1,mij+1,right);
}