#include <iostream>
#include <fstream>
#define MAX 100005
using namespace std;
ifstream f ("arbint.in");
ofstream g ("arbint.out");
int MaxArb[2*MAX],n,m,x,Val,Pos,Start,Finish,maxim,a,b;

int max (int a, int b)
{
    if (a>b) return a;
    else return b;
}
void Update(int nod, int left, int right)
{
    if (left==right)
    {
        MaxArb[nod]=Val;
        return;
    }
    int div=(left+right)/2;
    if (Pos<=div) Update(2*nod,left, div);
    else Update(2*nod+1, div+1,right);

    MaxArb[nod]=max(MaxArb[2*nod],MaxArb[2*nod+1]);
}
void Query(int nod, int left, int right)
{
    if (left>=Start && right <= Finish)
    {
        maxim=max(MaxArb[nod],maxim);
        return;
    }
    int div=(left+right)/2;
    if (Start <= div) Query(2*nod, left, div);
    if (div < Finish) Query(2*nod+1,div+1,right);
}
int main()
{
    f>>n>>m;
    for (int i=1;i<=n;i++)
    {
        f>>x;
        Pos=i;
        Val=x;
        Update(1,1,n);
    }
    for (int i=1;i<=m;i++)
    {
        f>>x>>a>>b;
        if (x)
        {
            Pos=a;
            Val=b;
            Update(1,1,n);
        }
        else
        {
            maxim=-1;
            Start=a;
            Finish=b;
            Query(1,1,n);
            g<<maxim<<'\n';
        }
    }
    return 0;
}