#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <complex>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#ifdef LOCAL
template <class T, size_t size = std::tuple_size<T>::value>
std::string to_debug(T, std::string s = "")
    requires(not std::ranges::range<T>);
std::string to_debug(auto x)
    requires requires(std::ostream& os) { os << x; }
{
    return static_cast<std::ostringstream>(std::ostringstream() << x).str();
}
std::string to_debug(std::ranges::range auto x, std::string s = "")
    requires(not std::is_same_v<decltype(x), std::string>)
{
    for (auto xi : x) {
        s += ", " + to_debug(xi);
    }
    return "[" + s.substr(s.empty() ? 0 : 2) + "]";
}
template <class T, size_t size>
std::string to_debug(T x, std::string s)
    requires(not std::ranges::range<T>)
{
    [&]<size_t... I>(std::index_sequence<I...>) { ((s += ", " + to_debug(get<I>(x))), ...); }(std::make_index_sequence<size>());
    return "(" + s.substr(s.empty() ? 0 : 2) + ")";
}
#define debug(...) std::cerr << __LINE__ << ": (" #__VA_ARGS__ ") = " << to_debug(std::tuple(__VA_ARGS__)) << "\n"
#else
#define debug(x...)
#endif

using i64 = long long;

void solve()
{
    
    int n; std::cin >> n;
    std::vector<std::string> deal(n); for (auto& di : deal) {std::cin >> di;}
    std::sort(std::begin(deal), std::end(deal), [&](auto& a, auto& b) { return std::size(a) < std::size(b); });
    std::unordered_set<std::string> S;
    int ans {}; for (auto& str : deal) {
        if (str.size() == 1) {
            S.insert(str);
            ans = std::max(ans, (int)str.size());
        } else {
            std::string s1, s2;
            s1 = str.substr(0, str.size() - 1);
            s2 = str.substr(1, str.size() - 1);
            if (S.contains(s1) and S.contains(s2)) {
                S.insert(str);
                ans = std::max(ans, (int)str.size());
            }
        }
    }

    std::cout << ans << "\n";
}

signed main()
{
    std::cin.tie(nullptr)->sync_with_stdio(false);
    int _ { 1 };
#ifdef tests
    std::cin >> _;
#endif
    while (_--)
        solve();
    return 0;
}