#include<fstream>
using namespace std;
int l[5002],v[5002],i,j,k,t,maxim,n;
int main()
{
	ifstream f("subsir2.in");
	ofstream g("subsir2.out");
	f>>n;
	for(i=1;i<=n;i++)
		f>>v[i];
	l[n]=1;
	for(i=n-1;i>0;i--)
	{
		maxim=0;
		for(k=i+1;k<=n;k++)
			if(v[k]>v[i]&&l[k]>maxim)
				maxim=l[k];
			l[i]=maxim+1;
	}
	for(i=1;i<=n;i++)
		if(maxim<l[i])
		{
			maxim=l[i];
			t=i;
		}
		g<<maxim<<"\n";
		//g<<t<<"\n";
			
	//for(i=1;i<=n;i++)
		//g<<l[i]<<" ";
	//g<<"\n";
	//for(i=1;i<=n;i++)
	//	g<<i<<" ";
	//g<<"\n";
	
	return 0;
}