#include <bits/stdc++.h>
using namespace std;
long long MOD = 998244353;
string alpha_upper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
string alpha_lower = "abcdefghijklmnopqrstuvwxyz";
double eps = 1e-12;
template <class T>
void print_array(T v[], long long size) {
  for (int i = 0; i < size; i++) {
    cout << v[i] << " ";
  }
  cout << endl;
}
template <class T1>
void print_vector(vector<T1> v, long long size) {
  for (int i = 0; i < size; i++) {
    cout << v[i] << " ";
  }
  cout << endl;
}
template <class Tm1, class Tm2>
void print_map(map<Tm1, Tm2> m) {
  for (auto it = m.begin(); it != m.end(); it++) {
    cout << (*it).first << " : " << (*it).second << endl;
  }
}
void solve() {
  long long n, k, m, x, y, total_msg_cost = 0;
  cin >> n >> k >> m;
  string s;
  map<string, long long> words_cost;
  map<long long, string> drakes;
  vector<long long> vy;
  for (long long i = 0; i < n; i += 1) {
    cin >> s;
    drakes[i] = s;
  }
  for (long long i = 0; i < n; i++) {
    cin >> y;
    words_cost[drakes[i]] = y;
  }
  while (k--) {
    cin >> x;
    for (long long i = 0; i < x; i++) {
      cin >> y;
      vy.push_back(y - 1);
    }
    y = -1;
    if (x > 1) {
      for (long long a : vy) {
        if (words_cost[drakes[y]] > words_cost[drakes[a]] || y == -1) y = a;
      }
      for (long long a : vy) {
        words_cost[drakes[a]] = words_cost[drakes[y]];
      }
    }
    if (x > 0) vy.clear();
  }
  for (long long i = 0; i < m; i += 1) {
    cin >> s;
    total_msg_cost += words_cost[s];
  }
  cout << total_msg_cost << endl;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  solve();
  return 0;
}
