// COCI 2016/2017 Contest 4 Rima
#include <bits/stdc++.h>
using namespace std;
#define _for(i, a, b) for (int i = (a); i < (int)(b); ++i)
const int SZ = 3e6 + 4, SG = 26;
int sz = 1, W[SZ], D[SZ], ch[SZ][SG];
void insert(const string &s) { // Trie插入字符串s
int u = 0;
for (char c : s) {
int &v = ch[u][c - 'a'];
if (!v) v = sz++;
u = v;
}
W[u] = 1; // u点对应单词结尾
} // D[u]:从u开始一路向右或者向下的最长链(必须路过单词点)
void dfs(int u, int &ans) {
int wv = 0, mx = 0, mx1 = 0; // wv: u的儿子中单词节点的个数
_for(i, 0, SG) if (ch[u][i]) {
int v = ch[u][i], &dv = D[v];
dfs(v, ans), wv += W[v];
if (mx < dv)
mx1 = mx, mx = dv;
else if (mx1 < dv)
mx1 = dv;
}
if (W[u]) D[u] = mx + max(wv, 1);
ans = max(ans, mx + mx1 + W[u] + max(wv - 2, 0));
}
int main() {
ios::sync_with_stdio(false), cin.tie(0);
int n, ans = 0;
cin >> n;
string s;
for (int i = 0; i < n and cin >> s; i++) reverse(begin(s), end(s)), insert(s);
dfs(0, ans), printf("%d\n", ans);
return 0;
}
