#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;

#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define rep(i, n) for (int i = 0; i < (n); i += 1)
#define len(a) ((int)(a).size())

mt19937 rnd(234);
const int inf = 1e8;

struct SGT {
    int n;
    vector<pair<int, int>> t;

    void build(vector<int> a) {
        n = 1;
        while (n < len(a)) {
            n *= 2;
        }
        t.resize(2 * n);
        rep(i, len(a)) {
            t[i + n] = {a[i], i};
        }
        for (int i = n - 1; i >= 0; i -= 1) {
            t[i] = min(t[i + i], t[i + i + 1]);
        }
    }

    pair<int, int> get(int l, int r) {
        l += n;
        r += n + 1;
        pair<int, int> rs = {inf + 1, -1};
        while (l < r) {
            if (l & 1) {
                rs = min(rs, t[l]);
                ++l;
            }
            if (r & 1) {
                --r;
                rs = min(rs, t[r]);
            }
            l /= 2;
            r /= 2;
        }
        return rs;
    }
};

int n;
vector<string> a;
vector<int> d;
SGT sgt;

bool cmp(const string &a, const string &b) {
    rep(i, max(len(a), len(b)) * 2) {
        if (a[i % len(a)] != b[i % len(b)]) {
            return (a[i % len(a)] < b[i % len(b)]);
        }
    }
    return false;
}

ll solve(ll l, ll r) {
    if (r - l + 1 < 3) {
        return 0;
    }
    auto [mn, pos] = sgt.get(l, r - 1);
    if (r == pos + 1) {
        return solve(l, pos);
    }
    auto [mn2, pos2] = sgt.get(pos + 1, r - 1);
    if (mn != mn2) {
        ll res1 = solve(l, pos);
        ll res2 = solve(pos + 1, r);
        return res1 + res2;
    }
    ll myres = ll(pos - l + 1) * (pos2 - pos) * (r - pos2);
    ll res1 = solve(l, pos);
    ll res2 = solve(pos + 1, pos2);
    ll res3 = solve(pos2 + 1, r);
    return myres + res1 + res2 + res3;
}

int32_t main() {
    if (1) {
        ios::sync_with_stdio(0);
        cin.tie(0);
        cout.tie(0);
    }
    cin >> n;
    a.resize(n);
    rep(i, n) {
        cin >> a[i];
    }
    sort(all(a), cmp);
    d.resize(n - 1);
    rep(i, n - 1) {
        d[i] = inf;
        for (int j = 0; j < max(len(a[i]), len(a[i + 1])) * 2; j += 1) {
            if (a[i][j % len(a[i])] != a[i + 1][j % len(a[i + 1])]) {
                d[i] = j;
                break;
            }
        }
    }
    sgt.build(d);
    ll result = solve(0, n - 1);
    cout << result << "\n";
    return 0;
}