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

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

#define MAX 110010

int a[2*MAX];
//se citeste un sir de numere si doua tipuri de operatii

//0 x y
//val de pe poz x devine y

//1 x y
//afisati maximul din intervalul (x, y)

int Pos, Val, start, end_the_variable;


void Update(int nod, int st, int dr)
{
    if(st==dr)
    {
        a[nod]=Val;
        return;
    }
    int ma=st+dr;
    ma>>=1;
    if(Pos<=ma)
        Update(2*nod, st, ma);
    else
        Update(2*nod+1, ma+1, dr);
    a[nod]=max(a[nod*2], a[nod*2+1]);
}

int Query(int nod, int st, int dr)
{
    if(start<=st && dr<=end_the_variable)
    {
        return a[nod];
    }
    if(end_the_variable<st || dr<start)
    {
        return -1;
    }
    int ma=(st+dr)>>1;
    return max(Query(2*nod, st, ma), Query(2*nod+1, ma+1, dr));
}



int main()
{
    int n, m;
    fin>>n>>m;
    int i, x, b, y;
    for(i=1;i<=n;i++)
    {
        fin>>x;
        Pos=i;
        Val=x;
        Update(1, 1, n);
    }
    while(m--)
    {
        fin>>b>>x>>y;
        if(b==1)
        {
            Pos=x;
            Val=y;
            Update(1, 1, n);
        }
        else
        {
            start=x;
            end_the_variable=y;
            fout<<Query(1, 1, n)<<"\n";
        }

    }


    return 0;
}