#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define pb push_back

const int N = 1e6;
int n;
map<ll, ll> dp;
vector<string> v;
ll pw[N], ans;
const ll mod = 1e9 + 7;
const ll p = 31;

main() {
	ios_base::sync_with_stdio(0), cin.tie(0);
	cin >> n;
	v.resize(n);
	for (int i = 0; i < n; ++i) cin >> v[i];
	/*sort(v.begin(), v.end(), [&](string a, string b) {
		return a.size() < b.size();
	});*/
	pw[0] = 1;
	for (int i = 1; i < N; ++i) {
		pw[i] = (pw[i - 1] * p) % mod;
	}
	for (auto d : v) {
		ll hsh = (d[0] - 'A' + 1);
		ll cnt = dp[hsh];
		for (int i = 1; i + 1 < (int)d.size(); ++i) hsh = (hsh + (d[i] - 'A' + 1) * pw[i] % mod) % mod, cnt = max(cnt, dp[hsh]);
		hsh = 0;
        for (int i = (int)d.size() - 1; i > 0; --i) hsh = (hsh * p % mod + (d[i] - 'A' + 1)) % mod, cnt = max(cnt, dp[hsh]);
		hsh = 0;
		for (int i = 0; i < (int)d.size(); ++i) hsh = (hsh + (d[i] - 'A' + 1) * pw[i] % mod) % mod;
		dp[hsh] = max(dp[hsh], cnt) + 1;
		ans = max(ans, dp[hsh]);
	}
	cout << ans << '\n';
	return 0;
}