Problem: Iahubina is tired of so many complicated languages, so she decided to invent a new, simple language. She already made a dictionary consisting of n 3-words. A 3-word is a sequence of exactly 3 lowercase letters of the first 24 letters of the English alphabet (a to x). She decided that some of the letters are vowels, and all the others are consonants. The whole language is based on a simple rule: any word that contains at least one vowel is correct.

Iahubina forgot which letters are the vowels, and wants to find some possible correct sets of vowels. She asks Iahub questions. In each question, she will give Iahub a set of letters considered vowels (in this question). For each question she wants to know how many words of the dictionary are correct, considering the given set of vowels.

Iahubina wants to know the xor of the squared answers to all the possible questions. There are 224 different questions, they are all subsets of the set of the first 24 letters of the English alphabet. Help Iahub find that number.

Input

The first line contains one integer, n (1 ≤ n ≤ 104). Each of the next n lines contains a 3-word consisting of 3 lowercase letters. There will be no two identical 3-words.

Output

Print one number, the xor of the squared answers to the queries.

Examples

Input

5
abc
aaa
ada
bcd
def


Output

0

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
const double pi = acos(0.0) * 2.0;
const double eps = 1e-12;
const int step[8][2] = {{1, 0}, {-1, 0}, {0, 1},  {0, -1},
                        {1, 1}, {1, -1}, {-1, 1}, {-1, -1}};
template <class T>
inline T abs1(T a) {
  return a < 0 ? -a : a;
}
template <class T>
inline T max1(T a, T b) {
  return a > b ? a : b;
}
template <class T>
inline T max1(T a, T b, T c) {
  return max1(max1(a, b), c);
}
template <class T>
inline T max1(T a, T b, T c, T d) {
  return max1(max1(a, b, c), d);
}
template <class T>
inline T max1(T a, T b, T c, T d, T e) {
  return max1(max1(a, b, c, d), e);
}
template <class T>
inline T min1(T a, T b) {
  return a > b ? a : b;
}
template <class T>
inline T min1(T a, T b, T c) {
  return min1(min1(a, b), c);
}
template <class T>
inline T min1(T a, T b, T c, T d) {
  return min1(min1(a, b, c), d);
}
template <class T>
inline T min1(T a, T b, T c, T d, T e) {
  return min1(min1(a, b, c, d), e);
}
template <class T>
inline T lowb(T num) {
  return num & (-num);
}
inline int jud(double a, double b) {
  if (abs(a) < eps && abs(b) < eps)
    return 0;
  else if (abs1(a - b) / abs1(a) < eps)
    return 0;
  if (a < b) return -1;
  return 1;
}
template <typename t>
inline int jud(t a, t b) {
  if (a < b) return -1;
  if (a == b) return 0;
  return 1;
}
template <typename it, typename t1>
inline int find(t1 val, it a, int na, bool f_small = 1, bool f_lb = 1) {
  int be = 0, en = na - 1;
  if (*a <= *(a + na - 1)) {
    if (f_lb == 0)
      while (be < en) {
        int mid = (be + en + 1) / 2;
        if (jud(*(a + mid), val) != 1)
          be = mid;
        else
          en = mid - 1;
      }
    else
      while (be < en) {
        int mid = (be + en) / 2;
        if (jud(*(a + mid), val) != -1)
          en = mid;
        else
          be = mid + 1;
      }
    if (f_small && jud(*(a + be), val) == 1) be--;
    if (!f_small && jud(*(a + be), val) == -1) be++;
  } else {
    if (f_lb)
      while (be < en) {
        int mid = (be + en + 1) / 2;
        if (jud(*(a + mid), val) != -1)
          be = mid;
        else
          en = mid - 1;
      }
    else
      while (be < en) {
        int mid = (be + en) / 2;
        if (jud(*(a + mid), val) != 1)
          en = mid;
        else
          be = mid + 1;
      }
    if (!f_small && jud(*(a + be), val) == -1) be--;
    if (f_small && jud(*(a + be), val) == 1) be++;
  }
  return be;
}
inline int bitnum(unsigned int nValue) { return __builtin_popcount(nValue); }
inline int bitnum(int nValue) { return __builtin_popcount(nValue); }
inline int bitnum(unsigned long long nValue) {
  return __builtin_popcount(nValue) + __builtin_popcount(nValue >> 32);
}
inline int bitnum(long long nValue) {
  return __builtin_popcount(nValue) + __builtin_popcount(nValue >> 32);
}
inline int bitmaxl(unsigned int a) {
  if (a) return 0;
  return 32 - __builtin_clz(a);
}
inline int bitmaxl(int a) {
  if (a) return 0;
  return 32 - __builtin_clz(a);
}
inline int bitmaxl(unsigned long long a) {
  int temp = a >> 32;
  if (temp) return 32 - __builtin_clz(temp) + 32;
  return bitmaxl(int(a));
}
inline int bitmaxl(long long a) {
  int temp = a >> 32;
  if (temp) return 32 - __builtin_clz(temp) + 32;
  return bitmaxl(int(a));
}
long long pow(long long n, long long m, long long mod = 0) {
  if (m < 0) return 0;
  long long ans = 1;
  long long k = n;
  while (m) {
    if (m & 1) {
      ans *= k;
      if (mod) ans %= mod;
    }
    k *= k;
    if (mod) k %= mod;
    m >>= 1;
  }
  return ans;
}
const int maxn = (1 << 24) + 10;
int cnt[maxn], n;
int arr[10010];
int main() {
  ios_base::sync_with_stdio(0);
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    char str[10];
    scanf("%s", str);
    int rmask = 0;
    for (int j = 0; j < 3; j++) rmask |= 1 << (str[j] - 'a');
    rmask = (1 << 24) - 1 - rmask;
    arr[i] = rmask;
    cnt[rmask]++;
  }
  long long ans = 0;
  for (int i = 23; i >= 0; i--) {
    int mask = 1 << 24;
    mask -= 1 + (1 << i);
    for (int j = mask; j >= 0; j = (j - 1) & mask) {
      cnt[j] += cnt[j + (1 << i)];
      if (j == 0) break;
    }
  }
  for (int i = (1 << 24) - 1; i >= 0; i--) {
    ans ^= (n - cnt[i]) * (n - cnt[i]);
  }
  cout << ans << endl;
  return 0;
}