#ifdef LOCAL111
	#define _GLIBCXX_DEBUG
#else
	#pragma GCC optimize ("O3")
	#define NDEBUG
#endif
// #define _USE_MATH_DEFINES
#include <bits/stdc++.h>
const int INF = 1e9;
using namespace std;
template<typename T, typename U> ostream& operator<< (ostream& os, const pair<T,U>& p) { os << '(' << p.first << ' ' << p.second << ')'; return os; }

#define endl '\n'
#define ALL(a)  (a).begin(),(a).end()
#define SZ(a) int((a).size())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n)  FOR(i,0,n)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
#ifdef LOCAL111
	#define DEBUG(x) cout<<#x<<": "<<(x)<<endl
	template<typename T> void dpite(T a, T b){ for(T ite = a; ite != b; ite++) cout << (ite == a ? "" : " ") << *ite; cout << endl;}
#else
	#define DEBUG(x) true
	template<typename T> void dpite(T a, T b){ return; }
#endif
#define F first
#define S second
#define SNP string::npos
#define WRC(hoge) cout << "Case #" << (hoge)+1 << ": "
template<typename T> void pite(T a, T b){ for(T ite = a; ite != b; ite++) cout << (ite == a ? "" : " ") << *ite; cout << endl;}
template<typename T> bool chmax(T& a, T b){if(a < b){a = b; return true;} return false;}
template<typename T> bool chmin(T& a, T b){if(a > b){a = b; return true;} return false;}

template<typename T>
vector<T> make_v(size_t a){return vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

template<typename T,typename U,typename... V>
typename enable_if<is_same<T, U>::value!=0>::type
fill_v(U &u,const V... v){u=U(v...);}

template<typename T,typename U,typename... V>
typename enable_if<is_same<T, U>::value==0>::type
fill_v(U &u,const V... v){
  for(auto &e:u) fill_v<T>(e,v...);
}

const array<int, 4> dx = {0, 1, 0, -1};
const array<int, 4> dy = {1, 0, -1, 0};


typedef long long int LL;
typedef unsigned long long ULL;
typedef pair<int,int> P;

void ios_init(){
	//cout.setf(ios::fixed);
	//cout.precision(12);
#ifdef LOCAL111
	return;
#endif
	ios::sync_with_stdio(false); cin.tie(0);
}

int main()
{
	ios_init();
	int n;
	while(cin >> n) {
		vector<string> s(n);
		REP(i, n) cin >> s[i];
		vector<LL> dp(SZ(s[0]) + 1);
		vector<LL> dpv(SZ(s[0]) + 1);
		LL ans = 0;
		ans += SZ(s[0]);
		dp[SZ(s[0])]++;
		dpv[SZ(s[0])]++;
		dpite(ALL(dp));
		dpite(ALL(dpv));
		FOR(i, 1, n) {
			DEBUG(i);
			vector<LL> nex(SZ(s[i]) + 1);
			vector<LL> nexv(SZ(s[i]) + 1);
			int l = min(SZ(s[i]), SZ(s[i - 1]));
			int ll = 0;
			REP(j, l) {
				if(s[i][j] != s[i - 1][j]) {
					break;
				}
				ll++;
			}
			REP(j, SZ(dp)) {
				nex[min(j, ll)] += dp[j];
				nexv[min(j, ll)] += dpv[j];
				nexv[min(j, ll)] += dp[j];
			}


			// FOR(j, ll, SZ(dp)) {
			// 	if(dp[j] != 0) {
			// 		nex[ll] += (dp[j] + 1);
			// 	}
			// }
			dp = nex;
			dpv = nexv;
			dp.back()++;
			dpv.back()++;
			REP(i, SZ(dp)) {
				ans += i * dpv[i];
			}
			dpite(ALL(dp));
			dpite(ALL(dpv));
		}
		cout << ans << endl;
	}
	return 0;
}