#include <bits/stdc++.h>
using namespace std;

#define int long long
#define rep(i, n) for (int i = 0; i < (int) (n); i++)
#define reps(i, n) for (int i = 1; i <= (int) (n); i++)
#define all(x) (x).begin(), (x).end()
#define uniq(x) (x).erase(unique(all(x)), (x).end())
#define bit(n) (1LL << (n))
#define dump(x) cerr << #x " = " << (x) << endl
using vint = vector<int>;
using vvint = vector<vint>;
using pint = pair<int, int>;
using vpint = vector<pint>;
template<typename T> using priority_queue_rev = priority_queue<T, vector<T>, greater<T>>;
constexpr double PI = 3.1415926535897932384626433832795028;
constexpr int DY[9] = {0, 1, 0, -1, 1, 1, -1, -1, 0};
constexpr int DX[9] = {1, 0, -1, 0, 1, -1, -1, 1, 0};
int sign(int x) { return (x > 0) - (x < 0); }
int gcd(int a, int b) {
    while (b) { swap(a %= b, b); }
    return a;
}
int lcm(int a, int b) { return a / gcd(a, b) * b; }
int cdiv(int a, int b) { return (a - 1 + b) / b; }
template<typename T> void fin(T mes) {
    cout << mes << endl;
    exit(0);
}
template<typename T, typename U> bool chmax(T &a, const U &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> bool chmin(T &a, const U &b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &rhs) {
    os << "(" << rhs.first << ", " << rhs.second << ")";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const vector<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const deque<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const set<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T, typename U> ostream &operator<<(ostream &os, const map<T, U> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
struct setup {
    static constexpr int PREC = 20;
    setup() {
        cout << fixed << setprecision(PREC);
        cerr << fixed << setprecision(PREC);
    };
} setup;

template<int K>
struct trie {
    std::vector<std::vector<int>> adj;
    std::vector<int> cnt;
    trie() : adj(1, std::vector<int>(K, -1)), cnt(1) {}
    void insert(const std::vector<int> &s) {
        int cur = 0;
        for (int c:s) {
            if (adj[cur][c] == -1) {
                adj[cur][c] = adj.size();
                adj.emplace_back(K, -1);
                cnt.emplace_back(0);
            }
            cur = adj[cur][c];
        }
        cnt[cur]++;
    }
    std::vector<int> count_prefix(const std::vector<int> &s) {
        std::vector<int> ret(s.size() + 1);
        int cur = 0;
        ret[0] = cnt[0];
        for (int i = 0; i < s.size(); i++) {
            if (adj[cur][s[i]] == -1) { break; }
            cur = adj[cur][s[i]];
            ret[i + 1] = cnt[cur];
        }
        return ret;
    }
};

signed main() {
    int N;
    cin >> N;
    vector<string> S(N);
    rep(i, N) { cin >> S[i], reverse(all(S[i])); }
    sort(all(S), [](string a, string b) { return a.length() < b.length(); });
    vector<trie<26>> tries(26);
    int ans = 0;
    rep(i, N) {
        vint s(all(S[i]));
        rep(j, s.size()) { s[j] -= 'a'; }
        rep(j, 26) {
            int idx = -1;
            rep(k, s.size()) { if (s[k] == j) { idx = k; }}
            vint res = tries[j].count_prefix(s);
            rep(k, idx + 1) { ans += res[k]; }
        }
        int b = s.back();
        s.pop_back();
        tries[b].insert(s);
    }
    cout << ans << endl;
}


Measured memory_bytes: 259100