#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cctype>
#include <chrono>
#include <cmath>
#include <complex>
#include <cstdint>
#include <cstdlib>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <type_traits>
#include <unordered_map>
#include <utility>
#include <vector>

/* template start */

using i64 = std::int_fast64_t;
using u64 = std::uint_fast64_t;

#define rep(i, a, b) for (i64 i = (a); (i) < (b); (i)++)
#define all(i) i.begin(), i.end()

#ifdef LOCAL
#define debug(...) \
  std::cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif

void debug_out() { std::cerr << std::endl; }

template <typename Head, typename... Tail>
void debug_out(Head h, Tail... t) {
  std::cerr << " " << h;
  if (sizeof...(t) > 0) std::cout << " :";
  debug_out(t...);
}

template <typename T1, typename T2>
std::ostream& operator<<(std::ostream& os, std::pair<T1, T2> pa) {
  return os << pa.first << " " << pa.second;
}

template <typename T>
std::ostream& operator<<(std::ostream& os, std::vector<T> vec) {
  for (std::size_t i = 0; i < vec.size(); i++)
    os << vec[i] << (i + 1 == vec.size() ? "" : " ");
  return os;
}

template <typename T1, typename T2>
inline bool chmax(T1& a, T2 b) {
  return a < b && (a = b, true);
}

template <typename T1, typename T2>
inline bool chmin(T1& a, T2 b) {
  return a > b && (a = b, true);
}

template <typename Num>
constexpr Num mypow(Num a, u64 b, Num id = 1) {
  if (b == 0) return id;
  Num x = id;
  while (b > 0) {
    if (b & 1) x *= a;
    a *= a;
    b >>= 1;
  }
  return x;
}

/* template end */

u64 popcount(u64 x) {
  x = (x & 0x5555555555555555ULL) + ((x & 0xAAAAAAAAAAAAAAAAULL) >> 1);
  x = (x & 0x3333333333333333ULL) + ((x & 0xCCCCCCCCCCCCCCCCULL) >> 2);
  x = (x & 0x0F0F0F0F0F0F0F0FULL) + ((x & 0xF0F0F0F0F0F0F0F0ULL) >> 4);

  x *= 0x0101010101010101ULL;

  return x >> 56;
}

int main() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);

  i64 n;
  std::cin >> n;

  std::vector<std::string> s(n);
  for (auto&& e : s) std::cin >> e;

  std::sort(all(s), [](const std::string& a, const std::string& b) {
    return a.size() < b.size();
  });

  rep(i, 0, n) std::reverse(all(s[i]));

  debug(s);

  struct Node;
  using node_ptr = Node*;
  struct Node {
    node_ptr next[26];
    u64 val;
    Node() : val(0) { std::fill(next, next + 26, nullptr); }
    ~Node() {
      rep(i, 0, 26) {
        if (next[i]) delete next[i];
        next[i] = nullptr;
      }
    }
  };

  node_ptr root = new Node();

  u64 ans = 0;

  for (const auto& e : s) {
    node_ptr now = root;
    i64 itr = 0;

    i64 tmp[26];
    u64 mask = 0;
    std::fill(tmp, tmp + 26, 0);
    rep(i, 0, e.size()) {
      if (tmp[e[i] - 'a'] == 0) mask += 1ull << (e[i] - 'a');
      tmp[e[i] - 'a']++;
    }

    while (now->next[e[itr] - 'a']) {
      ans+=popcount(mask&now->val);
      tmp[e[itr] - 'a']--;
      if(tmp[e[itr]-'a']==0)mask-=1ull<<(e[itr]-'a');
      now = now->next[e[itr] - 'a'];
      itr++;
    }
    ans+=popcount(mask&now->val);

    rep(i, itr, e.size() - 1) {
      node_ptr newnode = new Node();
      now->next[e[i] - 'a'] = newnode;
      now = newnode;
    }

    now->val+=1ull<<(e.back()-'a');
  }

  std::cout << ans << "\n";

  delete root;

  return 0;
}

Measured memory_bytes: 249596