#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vii = vector<int>;
using pii = pair<int, int>;
template <typename T = vii>
using vec = vector<T>;
const int N = 24;
const int MAX = 1 << N;
int f[MAX];
int main() {
  cin.tie(NULL);
  ios_base::sync_with_stdio(false);
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    string s;
    cin >> s;
    int j = 0;
    for (char c : s) {
      j |= 1 << (c - 'a');
    }
    f[j]++;
  }
  for (int i = 1; i < MAX; i <<= 1) {
    for (int mask = 0; mask < MAX; mask++) {
      if (mask & i) f[mask] += f[mask ^ i];
    }
  }
  ll res = 0;
  for (int mask = 0; mask < MAX; mask++) {
    ll ans = n - f[mask];
    ans *= ans;
    res ^= ans;
  }
  cout << res << '\n';
}
