#include <algorithm>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin ("arbint.in");
ofstream fout("arbint.out");
int n, m ,x ,y, i, sol, ok;
int a[300010];

void build(int nod, int st, int dr)
{
    if(st==dr)
        fin>>a[nod];
    else
    {
        int mid=(st+dr)/2;
        build(2*nod, st, mid);
        build(2*nod+1, mid+1, dr);
        a[nod]=max(a[2*nod], a[2*nod+1]);
    }
}

void update(int nod, int st, int dr, int poz, int val)
{
    if(st==dr)
        a[nod]=val;
    else
    {
        int mid=(st+dr)/2;
        if(poz<=mid)
            update(2*nod, st, mid, poz, val);
        if(poz>mid)
            update(2*nod+1, mid+1, dr, poz, val);
        a[nod]=max(a[2*nod], a[2*nod+1]);
    }
}

void vas(int nod, int st, int dr, int x, int y)
{
    if(x<=st&&y>=dr)
        sol=max(sol, a[nod]);
    else
    {
        int mid=(st+dr)/2;
        if(x<=mid)
            vas(2*nod, st, mid, x, y);
        if(mid+1<=y)
            vas(2*nod+1, mid+1, dr, x ,y);
    }
}

int main(){
    fin>>n>>m;
    build(1, 1, n);
    for(i=1;i<=m;i++)
    {
        fin>>ok>>x>>y;
        if(ok==0)
        {
            sol=0;
            vas(1, 1, n, x, y);
            fout<<sol<<"\n";
        }
        else
            update(1, 1 , n, x, y);
    }
    fin.close();
    fout.close();
    return 0;
}