//try with sqrt
#include <cstdio>
#include <cmath>
#include <algorithm>
using namespace std;
const int DIM=50000,nmax=100003,bmax=317;
int poz=DIM-1;
char buff[DIM];
void citeste(int &nr)
{
    nr=0;
    while(!('0'<=buff[poz]&&buff[poz]<='9'))
    {
        if(++poz==DIM) fread(buff,1,DIM,stdin),poz=0;
    }
    while('0'<=buff[poz]&&buff[poz]<='9')
    {
        nr=nr*10 + buff[poz]-'0';
        if(++poz==DIM) fread(buff,1,DIM,stdin),poz=0;
    }
}
int v[nmax],s[bmax];
unsigned char piece[nmax];
int n,m,x;
inline void citire()
{
    citeste(n),citeste(m);
    x=sqrt(n);
    for(int i=1;i<=n;i++) citeste(v[i]);
    int pieceT=0;
    for(int i=1;i<=n;i+=x)
    {
        ++pieceT;
        for(int j=i;j<i+x&&j<=n;j++)
        {
            piece[j]=pieceT;
            s[pieceT]=max(s[pieceT],v[j]);
        }
    }
}
int query1(int p1,int p2)
{
    int maxim=0;
    for(int i=p1;i<=p2;i++)
    {
        if(piece[i]!=piece[i-1]&&i+x-1<=p2)
        {
            maxim=max(maxim,s[piece[i]]);
            i+=x;
            --i;
        }
        else maxim=max(maxim,v[i]);
    }
    return maxim;
}
inline void solve()
{
    for(;m>0;--m)
    {
        int tip;
        citeste(tip);
        if(tip==1)
        {
            int a,b;
            citeste(a),citeste(b);
            v[a]=b;
            s[piece[a]]=0;
            for(int i=x*(piece[a]-1)+1;i<=x*(piece[a])&&i<=n;i++) s[piece[a]]=max(s[piece[a]],v[i]);
        }
        else
        {
            int a,b;
            citeste(a),citeste(b);
            printf("%d\n",query1(a,b));
        }

    }
}
int main()
{
    freopen ("arbint.in","r",stdin);
    freopen ("arbint.out","w",stdout);
    citire();
    solve();
}