#include <bits/stdc++.h>

using namespace std;

#define ll long long

const int mod = 998244353;
const int inf = 1e8;

void solve() {
  int n;
  cin >> n;
  vector<string> s(n);
  for (int i = 0; i < n; i++) cin >> s[i];

  vector<int> id(n);
  iota(id.begin(), id.end(), 0);
  sort(id.begin(), id.end(),
       [&](int x, int y) { return s[x].size() < s[y].size(); });

  map<string, bool> mp;

  int ans = 0;
  for (int i = 0; i < n; i++) {
    int j = id[i];
    if (s[j].size() == 1) {
      ans = 1;
      mp[s[j]] = true;
      continue;
    }
    string t1 = s[j].substr(0, s[j].size() - 1);
    string t2 = s[j].substr(1);
    if (mp[t1] && mp[t2]) {
      ans = s[j].size();
      mp[s[j]] = true;
    }
  }
  cout << ans << "\n";
}

signed main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cout << fixed << setprecision(10);
  int t = 1;
  // cin >> t;
  while (t--) solve();
  return 0;
}