#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
constexpr long long INF = 1LL << 60;
constexpr long long MOD = 1000000007;
double PI = acos(-1.0);
#define rep(i, n) for (ll i = 0; i < (n); ++i)
#define rep1(i, n) for (ll i = 1; i <= (n); ++i)
#define rrep(i, n) for (ll i = (n - 1); i >= 0; --i)
#define perm(c) sort(ALL(c));for(bool c##p=1;c##p;c##p=next_permutation(ALL(c)))
#define ALL(obj) (obj).begin(), (obj).end()
#define RALL(obj) (obj).rbegin(), (obj).rend()
#define pb push_back
#define to_s to_string
#define len(v) (ll)v.size()
#define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end())
#define print(x) cout << (x) << '\n'
#define drop(x) cout << (x) << '\n', exit(0)
#define debug(x) cout << #x << ": " << (x) << '\n'
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> P;
typedef tuple<ll, ll, ll> tpl;
typedef vector<ll> vec;
typedef vector<vector<ll>> vec2;
typedef vector<vector<vector<ll>>> vec3;
template<class S, class T> inline bool chmax(S &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class S, class T> inline bool chmin(S &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
inline ll msb(ll v) { return 1 << (31 - __builtin_clzll(v)); }
inline ll devc(ll x, ll y) { return (x + y - 1) / y; }
inline ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
inline ll lcm(ll a, ll b) { return a * (b / gcd(a, b)); }
 
struct IoSetup {
    IoSetup() {
        cin.tie(nullptr);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(10);
        cerr << fixed << setprecision(10);
    }
} iosetup;
 
template< typename T1, typename T2 >
ostream &operator << (ostream &os, const pair< T1, T2 > &p) {
    os << p.first << " " << p.second;
    return os;
}
 
template< typename T1, typename T2 >
istream &operator >> (istream &is, pair< T1, T2 > &p) {
    is >> p.first >> p.second;
    return is;
}
 
template< typename T1, typename T2, typename T3 >
ostream &operator << (ostream &os, const tuple< T1, T2, T3 > &t) {
    os << get<0>(t) << " " << get<1>(t) << " " << get<2>(t);
    return os;
}
 
template< typename T1, typename T2, typename T3 >
istream &operator >> (istream &is, tuple< T1, T2, T3 > &t) {
    is >> get<0>(t) >> get<1>(t) >> get<2>(t);
    return is;
}
 
template< typename T >
ostream &operator << (ostream &os, const vector< T > &v){
    for (int i = 0; i < (int)v.size(); ++i) {
        os << v[i] << (i + 1 != v.size() ? " " : "");
    }
    return os;
}
 
template< typename T >
istream &operator >>  (istream &is, vector< T > &v){
    for(T &in : v) is >> in;
    return is;
}

template< typename T >
ostream &operator << (ostream &os, const set< T > &st){
    int ct = 0;
    for(auto& s : st) cout << s << (++ct != st.size() ? " " : "");
    return os;
}

template <typename T>
constexpr set<T> &operator|= (set<T> &st1, const set<T> &st2) { 
    for(auto& s : st2) st1.insert(s);
    return st1; 
}

template <typename T>
constexpr set<T> &operator-= (set<T> &st1, const set<T> &st2) {
    for(auto& s : st2) if(st1.count(s)) st1.erase(s);
    return st1;
}

template <typename T>
constexpr set<T> &operator&= (set<T> &st1, const set<T> &st2) {
    auto itr = st1.begin();
    while(itr != st1.end()){
        if(!st2.count(*itr)) itr = st1.erase(itr);
        else ++itr;
    }
    return st1;
}

template <typename T>
constexpr set<T> operator| (const set<T> &st1, const set<T> &st2) {
    set<T> res = st1;
    res |= st2;
    return res;
}

template <typename T>
constexpr set<T> operator- (const set<T> &st1, const set<T> &st2) {
    set<T> res = st1;
    res -= st2;
    return res;
}

template <typename T>
constexpr set<T> operator& (const set<T> &st1, const set<T> &st2) {
    set<T> res = st1;
    res &= st2;
    return res;
}

/*---------------------------------    Tools    ------------------------------------------*/
template< typename T >
vector<T> cumsum(const vector<T> &X){
    vector<T> res(X.size() + 1, 0);
    for(int i = 0; i < X.size(); ++i) res[i + 1] += res[i] + X[i];
    return res;
}
 
template< typename S, typename T, typename F>
pair<T, T> bisearch(S left, T right, F f) {
    while(abs(right - left) > 1){
        T mid = (right + left) / 2;
        if(f(mid)) right = mid;
        else left = mid;
    }
    return {left, right};
}
 
template< typename S, typename T, typename F>
double trisearch(S left, T right, F f, int maxLoop = 90){
    double low = left, high = right;
    while(maxLoop--){
        double mid_left = high / 3 + low * 2 / 3;
        double mid_right = high * 2 / 3 + low / 3;
        if(f(mid_left) >= f(mid_right)) low = mid_left;
        else high = mid_right;
    }
    return (low + high) * 0.5;
}

template< typename F >
ll ternarySearch(ll L, ll R, F f) { //[L, R)
    ll lo = L - 1, hi = R - 1;
    while (lo + 1 != hi) {
        ll mi = (lo + hi) / 2;
        if (f(mi) <= f(mi + 1)) hi = mi;
        else lo = mi;
    }
    return hi;
}

struct xorShift128 {
    ull x = 123456789, y = 362436069, z = 521288629, w = 88675123;
    xorShift128(ull seed = 0) {
        w ^= seed;
    }
    ull operator()() {
        ull t = x ^ (x << 11);
        x = y; y = z; z = w;
        return w = (w ^ (w >> 19)) ^ (t ^ (t >> 8));
    }
};

xorShift128 xs(time(NULL));
const unsigned long long BASE = xs();
struct RollingHash {
    const ull MASK30 = (1ull << 30) - 1;
    const ull MASK31 = (1ull << 31) - 1;
    const ull MOD = (1ull << 61) - 1;
    const ull MASK61 = MOD;
    const ull POSITIVIZER = MOD * ((1ull << 3) - 1);

    vector<ull> hashed, power;

    RollingHash(const string& s) : hashed(s.size() + 1, 0), power(s.size() + 1, 0) {
        power[0] = 1;
        for (int i = 0; i < s.size(); ++i) power[i + 1] = CalcMod(Mul(power[i], BASE));
        for (int i = 0; i < s.size(); ++i) hashed[i + 1] = CalcMod(Mul(hashed[i], BASE) + s[i]);
    }

    ull get(int l, int r) {
        return CalcMod(hashed[r] + POSITIVIZER - Mul(hashed[l], power[r - l]));
    }

    ull Mul(ull a, ull b) {
        ull au = a >> 31;
        ull ad = a & MASK31;
        ull bu = b >> 31;
        ull bd = b & MASK31;
        ull mid = ad * bu + au * bd;
        ull midu = mid >> 30;
        ull midd = mid & MASK30;
        return au * bu * 2 + midu + (midd << 31) + ad * bd;
    }

    ull CalcMod(ull x) {
        ull xu = x >> 61;
        ull xd = x & MASK61;
        ull res = xu + xd;
        if (res >= MOD) res -= MOD;
        return res;
    }
};

/*------------------------------- Main Code Here -----------------------------------------*/
 
int main()
{
    ll N;
    cin >> N;
    vector<string> S(N);
    vector<set<ll>> st(27);
    cin >> S;
    for(auto &s : S){ 
        reverse(ALL(s));
        RollingHash RH(s);
        ll h = RH.get(0, len(s) - 1);
        st[s.back() - 'a'].insert(h);
    }

    ll ans = 0;
    for(auto &s : S){ 
        RollingHash RH(s);
        set<char> exist;
        --ans;
        while(!s.empty()){ 
            exist.insert(s.back());
            s.pop_back();
            for(auto e : exist) ans += st[e - 'a'].count(RH.get(0, len(s)));
        }
    }
    print(ans);

    return 0;
}

Measured memory_bytes: 20528