#include <iostream>
#include <fstream>
#define Nmax 300000
#include <algorithm>
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
int n,m,tree[Nmax],pos,val,maxim,start,finish,x,a,b;
void Update(int nod,int left, int right)
{
    if(left==right)
    {
        tree[nod]=val;
        return;
    }
    int mij=(left+right)/2;
    if(mij>=pos)Update(2*nod,left,mij);
    else Update(2*nod+1,mij+1,right);
    tree[nod]=max(tree[2*nod],tree[2*nod+1]);
}
void Query(int nod,int left,int right)
{
    if(right<=finish && left>=start)
    {
        if(maxim<tree[nod])maxim=tree[nod];
        return;
    }
    int mij=(left+right)/2;
    if(mij>=start)Query(2*nod,left,mij);
    if(mij<finish)Query(2*nod+1,mij+1,right);
}
int main()
{
    int i;
    fin>>n>>m;
    for(i=1;i<=n;++i)
    {
        fin>>val;
        pos=i;
        Update(1,1,n);
    }
    for(i=1;i<=m;++i)
    {
        fin>>x>>a>>b;
        if(x==0)
        {
            start=a;
            finish=b;
            maxim=-1;
            Query(1,1,n);
            fout<<maxim<<'\n';
        }
        else{
            pos=a;
            val=b;
            Update(1,1,n);
        }
    }
    return 0;
}