After learning a lot about space exploration, a little girl named Ana wants to change the subject.

Ana is a girl who loves palindromes (string that can be read the same backwards as forward). She has learned how to check for a given string whether it's a palindrome or not, but soon she grew tired of this problem, so she came up with a more interesting one and she needs your help to solve it:

You are given an array of strings which consist of only small letters of the alphabet. Your task is to find how many palindrome pairs are there in the array. A palindrome pair is a pair of strings such that the following condition holds: at least one permutation of the concatenation of the two strings is a palindrome. In other words, if you have two strings, let's say "aab" and "abcac", and you concatenate them into "aababcac", we have to check if there exists a permutation of this new string such that it is a palindrome (in this case there exists the permutation "aabccbaa"). 

Two pairs are considered different if the strings are located on different indices. The pair of strings with indices (i,j) is considered the same as the pair (j,i).

Input

The first line contains a positive integer N (1 ≤ N ≤ 100 000), representing the length of the input array.

Eacg of the next N lines contains a string (consisting of lowercase English letters from 'a' to 'z') — an element of the input array. 

The total number of characters in the input array will be less than 1 000 000.

Output

Output one number, representing how many palindrome pairs there are in the array.

Examples

Input

3
aa
bb
cd


Output

1


Input

6
aab
abcac
dffe
ed
aa
aade


Output

6

Note

The first example:

  1. aa + bb → abba. 



The second example:

  1. aab + abcac = aababcac → aabccbaa
  2. aab + aa = aabaa
  3. abcac + aa = abcacaa → aacbcaa
  4. dffe + ed = dffeed → fdeedf
  5. dffe + aade = dffeaade → adfaafde
  6. ed + aade = edaade → aeddea
#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx")
#pragma GCC optimize("unroll-loops")
using namespace std;
using ll = long long;
using ld = long double;
using db = double;
using str = string;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<double, double>;
using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<double>;
using vs = vector<string>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vpd = vector<pd>;
const int di[4] = {-1, 0, 1, 0}, dj[4] = {0, 1, 0, -1};
const int di8[8] = {-1, -1, 0, 1, 1, 1, 0, -1},
          dj8[8] = {0, 1, 1, 1, 0, -1, -1, -1};
const ld PI = acos((ld)-1);
const ll INF = 1e18;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll randint(ll a, ll b) { return uniform_int_distribution<ll>(a, b)(rng); }
bool pow2(int i) { return i && (i & -i) == i; }
constexpr int pct(int x) { return __builtin_popcount(x); }
constexpr int bits(int x) { return 31 - __builtin_clz(x); }
ll cdiv(ll a, ll b) { return a / b + ((a ^ b) > 0 && a % b); }
ll fdiv(ll a, ll b) { return a / b - ((a ^ b) < 0 && a % b); }
ll half(ll x) { return fdiv(x, 2); }
bool inc(ll a, ll b, ll c) { return a <= b && b <= c; }
template <class T>
bool chmin(T& a, const T& b) {
  return b < a ? a = b, 1 : 0;
}
template <class T>
bool chmax(T& a, const T& b) {
  return a < b ? a = b, 1 : 0;
}
template <class T>
void remDup(vector<T>& v) {
  sort((v).begin(), (v).end());
  v.erase(unique((v).begin(), (v).end()), end(v));
}
template <class T, class U>
void remAll(vector<T>& v, U a) {
  v.erase(remove((v).begin(), (v).end(), a), v.end());
}
template <class T, class U>
T fstTrue(T lo, T hi, U f) {
  while (lo < hi) {
    T mid = half(lo + hi);
    f(mid) ? hi = mid : lo = mid + 1;
  }
  return lo;
}
template <class T, class U>
T lstTrue(T lo, T hi, U f) {
  while (lo < hi) {
    T mid = half(lo + hi + 1);
    f(mid) ? lo = mid : hi = mid - 1;
  }
  return lo;
}
template <class T, class U, class C>
string to_string(tuple<T, U, C> p);
template <class T, class U, class C, class D>
string to_string(tuple<T, U, C, D> p);
string to_string(char c) { return string(1, c); }
string to_string(bool b) { return to_string((int)b); }
string to_string(const char* s) { return (string)s; }
string to_string(string s) { return s; }
template <class T>
string to_string(complex<T> c) {
  stringstream ss;
  ss << c;
  return ss.str();
}
string to_string(vb v) {
  string res = "{";
  for (int i = (0); i < (((int)(v).size())); ++i) res += char('0' + v[i]);
  res += "}";
  return res;
}
template <size_t SZ>
string to_string(bitset<SZ> b) {
  string res = "";
  for (int i = (0); i < (((int)(b).size())); ++i) res += char('0' + b[i]);
  return res;
}
template <class T, class U>
string to_string(pair<T, U> p);
template <class T>
string to_string(T v) {
  bool fst = 1;
  string res = "";
  for (const auto& x : v) {
    if (!fst) res += " ";
    fst = 0;
    res += to_string(x);
  }
  return res;
}
template <class T, class U>
string to_string(pair<T, U> p) {
  return to_string(p.first) + " " + to_string(p.second);
}
template <class T, class U, class C>
string to_string(tuple<T, U, C> p) {
  return to_string(get<0>(p)) + " " + to_string(get<1>(p)) + " " +
         to_string(get<2>(p));
}
template <class T, class U, class C, class D>
string to_string(tuple<T, U, C, D> p) {
  return to_string(get<0>(p)) + " " + to_string(get<1>(p)) + " " +
         to_string(get<2>(p)) + " " + to_string(get<3>(p));
}
template <class T, class U, class C>
void re(tuple<T, U, C>& p);
template <class T, class U, class C, class D>
void re(tuple<T, U, C, D>& p);
template <class T>
void re(complex<T>& c);
template <class T, class U>
void re(pair<T, U>& p);
template <class T>
void re(vector<T>& v);
template <class T, size_t SZ>
void re(array<T, SZ>& a);
template <class T>
void re(T& x) {
  cin >> x;
}
void re(double& d) {
  string t;
  re(t);
  d = stod(t);
}
void re(ld& d) {
  string t;
  re(t);
  d = stold(t);
}
template <class T, class... U>
void re(T& t, U&... u) {
  re(t);
  re(u...);
}
template <class T>
void re(complex<T>& c) {
  T a, b;
  re(a, b);
  c = {a, b};
}
template <class T, class U>
void re(pair<T, U>& p) {
  re(p.first, p.second);
}
template <class T>
void re(vector<T>& x) {
  for (auto& a : x) re(a);
}
template <class T, size_t SZ>
void re(array<T, SZ>& x) {
  for (auto& a : x) re(a);
}
template <class T, class U, class C>
void re(tuple<T, U, C>& p) {
  re(get<0>(p), get<1>(p), get<2>(p));
}
template <class T, class U, class C, class D>
void re(tuple<T, U, C, D>& p) {
  re(get<0>(p), get<1>(p), get<2>(p), get<3>(p));
}
template <class T>
void pr(T x) {
  cout << to_string(x);
}
template <class T, class... U>
void pr(const T& t, const U&... u) {
  pr(t);
  pr(u...);
}
void ps() { pr("\n"); }
template <class T, class... U>
void ps(const T& t, const U&... u) {
  pr(t);
  if (sizeof...(u)) pr(" ");
  ps(u...);
}
void DBG() { cerr << "]" << endl; }
template <class T, class... U>
void DBG(const T& t, const U&... u) {
  cerr << to_string(t);
  if (sizeof...(u)) cerr << ", ";
  DBG(u...);
}
struct chash {
  const uint64_t C = ll(2e18 * PI) + 71;
  const int RANDOM = rng();
  ll operator()(ll x) const { return __builtin_bswap64((x ^ RANDOM) * C); }
};
template <class T>
using V = vector<T>;
template <class T, size_t SZ>
using AR = array<T, SZ>;
template <class T>
using mpq = priority_queue<T, vector<T>, greater<T>>;
template <class T>
using pq = priority_queue<T>;
template <class T, class U>
using um = unordered_map<T, U, chash>;
template <class T>
using us = unordered_set<T, chash>;
template <class T>
using PR = pair<T, T>;
const int MOD = 998244353;
template <int MOD, int RT>
struct mint {
  static const int mod = MOD;
  static constexpr mint rt() { return RT; }
  int v;
  explicit operator int() const { return v; }
  mint() { v = 0; }
  mint(ll _v) {
    v = (-MOD < _v && _v < MOD) ? _v : _v % MOD;
    if (v < 0) v += MOD;
  }
  friend bool operator==(const mint& a, const mint& b) { return a.v == b.v; }
  friend bool operator!=(const mint& a, const mint& b) { return !(a == b); }
  friend bool operator<(const mint& a, const mint& b) { return a.v < b.v; }
  friend void re(mint& a) {
    ll x;
    re(x);
    a = mint(x);
  }
  friend string to_string(mint a) { return to_string(a.v); }
  mint& operator+=(const mint& m) {
    if ((v += m.v) >= MOD) v -= MOD;
    return *this;
  }
  mint& operator-=(const mint& m) {
    if ((v -= m.v) < 0) v += MOD;
    return *this;
  }
  mint& operator*=(const mint& m) {
    v = (ll)v * m.v % MOD;
    return *this;
  }
  mint& operator/=(const mint& m) { return (*this) *= inv(m); }
  friend mint pow(mint a, ll p) {
    mint ans = 1;
    assert(p >= 0);
    for (; p; p /= 2, a *= a)
      if (p & 1) ans *= a;
    return ans;
  }
  friend mint inv(const mint& a) {
    assert(a.v != 0);
    return pow(a, MOD - 2);
  }
  mint operator-() const { return mint(-v); }
  mint& operator++() { return *this += 1; }
  mint& operator--() { return *this -= 1; }
  friend mint operator+(mint a, const mint& b) { return a += b; }
  friend mint operator-(mint a, const mint& b) { return a -= b; }
  friend mint operator*(mint a, const mint& b) { return a *= b; }
  friend mint operator/(mint a, const mint& b) { return a /= b; }
};
typedef mint<MOD, 5> mi;
vector<vector<mi>> scmb;
void genComb(int SZ) {
  scmb.assign(SZ, vector<mi>(SZ));
  scmb[0][0] = 1;
  for (int i = (1); i < (SZ); ++i)
    for (int j = (0); j < (i + 1); ++j)
      scmb[i][j] = scmb[i - 1][j] + (j ? scmb[i - 1][j - 1] : 0);
}
vi invs, fac, ifac;
void genFac(int SZ) {
  invs.resize(SZ), fac.resize(SZ), ifac.resize(SZ);
  invs[1] = fac[0] = ifac[0] = 1;
  for (int i = (2); i < (SZ); ++i)
    invs[i] = MOD - (ll)MOD / i * invs[MOD % i] % MOD;
  for (int i = (1); i < (SZ); ++i) {
    fac[i] = (ll)fac[i - 1] * i % MOD;
    ifac[i] = (ll)ifac[i - 1] * invs[i] % MOD;
  }
}
mi comb(int a, int b) {
  if (a < b || b < 0) return 0;
  return (ll)fac[a] * ifac[b] % MOD * ifac[a - b] % MOD;
}
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
using ul = unsigned long long;
ul modMul(ul a, ul b, const ul mod) {
  ll ret = a * b - mod * (ul)((ld)a * b / mod);
  return ret + ((ret < 0) - (ret >= (ll)mod)) * mod;
}
ul modPow(ul a, ul b, const ul mod) {
  if (b == 0) return 1;
  ul res = modPow(a, b / 2, mod);
  res = modMul(res, res, mod);
  return b & 1 ? modMul(res, a, mod) : res;
}
bool prime(ul n) {
  if (n < 2 || n % 6 % 4 != 1) return n - 2 < 2;
  ul A[] = {2, 325, 9375, 28178, 450775, 9780504, 1795265022},
     s = __builtin_ctzll(n - 1), d = n >> s;
  for (auto& a : A) {
    ul p = modPow(a, d, n), i = s;
    while (p != 1 && p != n - 1 && a % n && i--) p = modMul(p, p, n);
    if (p != n - 1 && i != s) return 0;
  }
  return 1;
}
void setIn(string s) { freopen(s.c_str(), "r", stdin); }
void setOut(string s) { freopen(s.c_str(), "w", stdout); }
void IOS(int n = 10, string s = "") {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cout.precision(n);
  cerr.precision(n);
  cerr << fixed;
  cout << fixed;
  if (((int)(s).size())) {
    setIn(s + ".in"), setOut(s + ".out");
  }
}
const int mxN = 3e5 + 5;
void solve(int tt) {
  int n;
  ll ans = 0;
  re(n);
  um<int, int> m;
  for (int i = (0); i < (n); ++i) {
    str s;
    re(s);
    int x = 0;
    for (auto& j : s) x ^= 1 << (j - 'a');
    ans += m[x];
    for (int j = (0); j < (26); ++j) ans += m[x ^ (1 << j)];
    m[x]++;
  }
  ps(ans);
}
int main() {
  IOS();
  int t = 1;
  for (int i = (0); i < (t); ++i) {
    solve(i + 1);
  }
}
