#include <bits/stdc++.h>
using namespace std;
const int MAXN = 8;
const int MAXR = 1;
const int MAXC = 1;
const int INF = (int)1e9;
priority_queue<int, vector<int>, greater<int>> q1;
priority_queue<int, vector<int>, less<int>> q2;
int arr[MAXN];
map<int, int> m1;
map<string, int> m2;
vector<pair<string, pair<int, int>>> v;
int n, m, k;
int dx[] = {-1, 0, 1, 0};
int dy[] = {0, 1, 0, -1};
int main(void) {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> n >> k >> m;
  int x, y;
  string s;
  v.resize(n + 1);
  for (int i = 0; i < n; ++i) {
    cin >> s;
    v[i + 1] = make_pair(s, make_pair(i + 1, 0));
  }
  for (int i = 0; i < n; ++i) {
    cin >> x;
    v[i + 1].second.second = x;
  };
  ;
  for (int i = 0; i < k; ++i) {
    int gn = i + 1;
    cin >> x;
    m1[gn] = INF;
    for (int j = 0; j < x; ++j) {
      cin >> y;
      pair<string, pair<int, int>> p1 = v[y];
      pair<int, int> p2 = p1.second;
      if (p2.second < m1[gn]) {
        m1[gn] = p2.second;
      }
      m2[p1.first] = gn;
    }
  };
  ;
  long long int tc = 0;
  for (int i = 0; i < m; ++i) {
    cin >> s;
    int gn = m2[s];
    int mc = m1[gn];
    tc += mc * 1LL;
  }
  cout << tc;
  return 0;
}
