#include <iostream>
#include <sstream>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <memory>
#include <complex>
#include <numeric>
#include <cstdio>
#include <iomanip>
#include <random>
#include <unordered_map>

#define REP(i,m,n) for(int i=int(m);i<int(n);i++)
#define RREP(i,m,n) for(int i=int(n)-1;i>=int(m);--i)
#define EACH(i,c) for (auto &(i): c)
#define all(c) begin(c),end(c)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort(begin(c),end(c))
#define pb emplace_back
#define MP make_pair
#define SZ(a) int((a).size())
//#define int long long

#ifdef LOCAL
#define DEBUG(s) cout << (s) << endl
#define dump(x)  cerr << #x << " = " << (x) << endl
#define BR cout << endl;
#else
#define DEBUG(s) do{}while(0)
#define dump(x) do{}while(0)
#define BR 
#endif
using namespace std;

using UI = unsigned int;
using UL = unsigned long;
using LL = long long;
using ULL = unsigned long long;
using VI = vector<int>;
using VVI = vector<VI>;
using VLL = vector<LL>;
using VVLL = vector<VLL>;
using VS = vector<string>;
using PII = pair<int,int>;
using VP = vector<PII>;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

struct Node {
    bool isend;
    unordered_map<char, Node*> m;
    Node(): isend(false) {}
};
class Trie {
public:
    Node* root;
    /** Initialize your data structure here. */
    Trie(): root(new Node()) {
        
    }
    
    /** Inserts a word into the trie. */
    void insert(string word) {
        Node *node = root;
        REP(i,0,word.size()) {
            char c = word[i];
            if (node->m.count(c) == 0) node->m[c] = new Node();

            node = node->m[c];
        }

        node->isend = true;
    }
    
    /** Returns if the word is in the trie. */
    bool search(string word) {        
        Node *node = root;
        for (char c: word) {
            if (node->m.count(c) == 0) return false;
            node = node->m[c];
        }
        return node->isend;
    }
    
    /** Returns if there is any word in the trie that starts with the given prefix. */
    bool startsWith(string prefix) {        
        Node *node = root;
        for (char c: prefix) {
            if (node->m.count(c) == 0) return false;
            node = node->m[c];
        }
        return true;
    }
};

void solve() {
    int n;
    cin >> n;
    VS ss(n);
    REP(i,0,n) cin >> ss[i];
    vector<vector<int>> ds(n);
    REP(i,0,n) {
        int p = 0;
        REP(j,0,ss[i].size()) {
            p |= (1<<(ss[i][j] - 'a'));
            ds[i].emplace_back(p);
        }
        reverse(all(ds[i]));
    }

    REP(i,0,n) reverse(all(ss[i]));
    Trie t;
    REP(i,0,n) t.insert(ss[i]);

    LL cnt = 0;
    REP(i,0,n) {
        // dump(i);
        Node *node = t.root;
        REP(j,0,ss[i].size()-1) {
            char c = ss[i][j];
            // if (node->isend) ++cnt;
            REP(k,0,26) {
                char d = char('a'+k);
                if (d == c) continue;
                // if (ds[i][j].count(d) == 0) continue;
                if (!(ds[i][j] & (1<<k))) continue;
                if (node->m.count(d) == 0) continue;
                if (!node->m[d]->isend) continue;
                ++cnt;
            }
            if (node->m.count(c) == 0) break;
            node = node->m[c];
            if (node->isend) ++cnt;
        }
        // dump(cnt);
    }
    cout << cnt << endl;
}

signed main() {
    solve();
    
    return 0;
}

Measured memory_bytes: 150824