#include <fstream>

using namespace std;
ifstream f("subsir2.in");
ofstream g("subsir2.out");
int a[5005],l[5005],n;
void solve()
{
    int i,j,mn,poz,val;
    for(i=n-1;i>=1;i--)
    {
        mn=1000005;
        poz=n+1;
        val=1000005;
        for(j=i+1;j<=n;j++)
        {
            if(a[j]>a[i]&&l[j]<mn&&a[j]<val)
            {
                val=a[j];
                mn=l[j];
                poz=j;
            }
        }
        if(poz>n) l[i]=1;
        else l[i]=1+mn;
    }

}
int main()
{
    int mn=1000005,i,mx=0;
    f>>n;
    for(i=1;i<=n;i++) f>>a[i];
    l[n]=1;
    solve();
    for(i=1;i<=n;i++)
    {
        if(l[i]>mx) mx=l[i];
    }
    g<<mx<<" ";
    return 0;
}