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

#define rep(i, m, n) for(int(i) = (int)(m); i < (int)(n); ++i)
#define rep2(i, m, n) for(int(i) = (int)(n)-1; i >= (int)(m); --i)
#define REP(i, n) rep(i, 0, n)
#define REP2(i, n) rep2(i, 0, n)
#define all(hoge) (hoge).begin(), (hoge).end()
#define en '\n'
using ll = long long;
using ull = unsigned long long;
template <class T>
using vec = vector<T>;
template <class T>
using vvec = vector<vec<T>>;
typedef pair<ll, ll> P;
using tp = tuple<ll, ll, ll>;
constexpr long long INF = 1LL << 60;
constexpr int INF_INT = 1 << 25;
//constexpr long long MOD = (ll)1e9 + 7;
constexpr long long MOD = 998244353LL;
using ld = long double;
static const ld pi = 3.141592653589793L;
typedef vector<ll> Array;
typedef vector<Array> Matrix;

template <class T>
inline bool chmin(T &a, T b) {
    if(a > b) {
        a = b;
        return true;
    }
    return false;
}
template <class T>
inline bool chmax(T &a, T b) {
    if(a < b) {
        a = b;
        return true;
    }
    return false;
}

//グラフ関連
struct Edge {
    ll to, cap, rev;
    Edge(ll _to, ll _cap, ll _rev) {
        to = _to;
        cap = _cap;
        rev = _rev;
    }
};
typedef vector<Edge> Edges;
typedef vector<Edges> Graph;

void add_edge(Graph &G, ll from, ll to, ll cap, bool revFlag, ll revCap) {
    G[from].push_back(Edge(to, cap, (ll)G[to].size()));
    if(revFlag)
        G[to].push_back(Edge(from, revCap, (ll)G[from].size() - 1));
}

class Trie {
  private:
    vvec<int> nxt;
    vec<int> end;  //suffix link,そのノードに存在する文字列の数
    vec<int> last; //その文字にとって最後のアルファベットだけ数える
    int root, p;
    int maxn; //文字の合計サイズ
    vvec<int> con;

  public:
    Trie(int maxn) : maxn(maxn), nxt(maxn, vec<int>(26, -1)), end(maxn, 0), last(maxn, 0), p(1), root(0), con(maxn, vec<int>(26, 0)) {}

    void insert(const string &s) {
        ll m = s.size();
        vec<bool> used(26, false);
        vec<bool> las(m, 0);
        REP2(i, m) {
            if(used[s[i] - 'a'])
                continue;
            used[s[i] - 'a'] = true;
            las[i] = true;
        }

        int now = root;
        for(int i = 0; i < s.size(); i++) {
            if(nxt[now][s[i] - 'a'] == -1)
                nxt[now][s[i] - 'a'] = p++;
            now = nxt[now][s[i] - 'a'];
            if(las[i])
                last[now]++;
        }
        end[now]++;
    }

    ll dfs(int now) {
        vec<ll> cone(26, 0);
        ll ret = 0;
        REP(i, 26) {
            if(nxt[now][i] == -1)
                continue;
            ret += dfs(nxt[now][i]);
            cone[i] += end[nxt[now][i]];

            con[now][i] += last[nxt[now][i]];
            REP(j, 26) {
                con[now][j] += con[nxt[now][i]][j];
            }
        }

        REP(i, 26) {
            if(cone[i] == 0)
                continue;
            ret += (con[now][i] - cone[i]) * cone[i];
        }

        return ret;
    }
};

void solve() {
    ll n;
    cin >> n;
    Trie tr(1010101);
    vec<string> s(n);
    REP(i, n) {
        cin >> s[i];
        reverse(all(s[i]));
        tr.insert(s[i]);
    }
    cout << tr.dfs(0) << en;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    /*
    ll t;
    cin >> t;
    while(t--)*/
    solve();

    return 0;
}


Measured memory_bytes: 538504