#include <set>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
int main() {
	int N;
	cin >> N;
	vector<string> S(N);
	for (int i = 0; i < N; ++i) {
		cin >> S[i];
	}
	vector<int> A(N - 1);
	for (int i = 1; i < N; ++i) {
		int lcp = 0;
		for (int j = 0; j < S[i - 1].size() && j < S[i].size(); ++j) {
			if (S[i][j] != S[i - 1][j]) break;
			++lcp;
		}
		A[i - 1] = lcp;
	}
	vector<int> p(N - 1);
	for (int i = 0; i < N - 1; ++i) {
		p[i] = i;
	}
	sort(p.begin(), p.end(), [&](int i, int j) { return A[i] < A[j]; });
	set<int> s;
	s.insert(-1);
	s.insert(N - 1);
	long long ans = 0;
	for (int i = 0; i < N - 1; ++i) {
		set<int>::iterator it = s.lower_bound(p[i]);
		int r = *it, l = *(--it);
		ans += 1LL * (A[p[i]]) * (r - p[i]) * (p[i] - l) * (r - l + 2) / 2;
		s.insert(p[i]);
	}
	for (int i = 0; i < N; ++i) {
		ans += S[i].size();
	}
	cout << ans << endl;
	return 0;
}