#include <bits/stdc++.h>
using namespace std;
double EPS = 1e-9;
long long INF = 1000000000000000005ll;
double PI = acos(-1);
inline string IntToString(long long int a) {
  char x[100];
  sprintf(x, "%lld", a);
  string s = x;
  return s;
}
inline long long int StringToInt(string a) {
  char x[100];
  long long int res;
  strcpy(x, a.c_str());
  sscanf(x, "%lld", &res);
  return res;
}
inline string uppercase(string s) {
  int n = (int)s.size();
  for (long long int i = 0; i < n; i++)
    if (s[i] >= 'a' && s[i] <= 'z') s[i] = s[i] - 'a' + 'A';
  return s;
}
inline string lowercase(string s) {
  int n = (int)s.size();
  for (long long int i = 0; i < n; i++)
    if (s[i] >= 'A' && s[i] <= 'Z') s[i] = s[i] - 'A' + 'a';
  return s;
}
bool sortcol(const vector<long long int>& v1, const vector<long long int>& v2) {
  return v1[0] > v2[0];
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long int n;
  cin >> n;
  long long int c[n];
  string r[n];
  string s[n];
  for (long long int i = 0; i < n; i++) cin >> c[i];
  for (long long int i = 0; i < n; i++) {
    cin >> r[i];
    s[i] = r[i];
    reverse(r[i].begin(), r[i].end());
  }
  long long int dp[n + 1][2];
  memset(dp, 0, sizeof(dp));
  dp[0][1] = c[0];
  for (long long int i = 1; i < n; i++) {
    dp[i][0] = INF;
    dp[i][1] = INF;
    if (s[i] >= s[i - 1]) {
      dp[i][0] = min(dp[i - 1][0], dp[i][0]);
    }
    if (s[i] >= r[i - 1]) {
      dp[i][0] = min(dp[i - 1][1], dp[i][0]);
    }
    if (r[i] >= s[i - 1]) {
      dp[i][1] = min(dp[i - 1][0] + c[i], dp[i][1]);
    }
    if (r[i] >= r[i - 1]) {
      dp[i][1] = min(dp[i - 1][1] + c[i], dp[i][1]);
    }
  }
  long long int mi = min(dp[n - 1][0], dp[n - 1][1]);
  if (mi != INF)
    cout << min(dp[n - 1][0], dp[n - 1][1]) << '\n';
  else
    cout << -1 << '\n';
  return 0;
}
