/*
https://vijos.org/p/1028
*/
#include<iostream>
#include<cstdio>
#include<cstring>
#define rep(i,x,y) if ((x)<=(y)) for (register int i=(x);i<=(y);i++)
using namespace std;
bool pd(string s1,string s2)
{
	rep(i,0,s1.length()-1)
	  if (s1[i]!=s2[i])
	    return false;
	return true;
}
	
int main()
{
	int n,f[10000],ans=0;
	string s[10000];
	cin>>n;
	rep(i,1,n)
	  f[i]=1;
	rep(i,1,n)
	  cin>>s[i];
	rep(i,1,n)
	  rep(j,1,i-1)
	  {
	  	if (s[j].length()>s[i].length())
	  	  continue;
	  	if (pd(s[j],s[i]) and f[j]>f[i]-1)
		  f[i]=f[j]+1;
	  }
	rep(i,1,n)
	  ans=max(ans,f[i]);
	cout<<ans;
	return 0;
}