# include <stdio.h>
int n,max;
int a[5005],lung[5005],ant;
void solve ()
{
	int i,j,k;
	scanf ("%d",&n);
	for (i=1; i<=n; ++i)
		scanf ("%d",&a[i]);
	for (i=1; i<=n; ++i)
	{
		max=0;
		for (j=1; j<i; ++j)
			if (lung[j]>=max && a[i]>a[j])
			{
				max=lung[j];
				k=j;
			}
		lung[i]=lung[k]+1;
	}
	for (j=1; j<=n; ++j)
			if (lung[j]>max)
				max=lung[j];
    printf ("%d",max);
}
int main ()
{
	freopen ("scmax.in","r",stdin);
	freopen ("scmax.out","w",stdout);
	solve ();
    return 0;
}