#include <bits/stdc++.h>
using namespace std;
const long long maxn = (long long)1e5 + 7;
const long long linf = (long long)1e18 + 7;
const long long INF = (long long)1e9 + 7;
const long double pi = 3.14159265359;
const double eps = 1e-6;
const long long base = 1000 * 1000 * 1000;
const long long P = 37;
const long long block = 547;
long long n, m, a[maxn], c[maxn], ans, k;
int parent[600000], ran[600000];
vector<long long> v[maxn];
void boost() {
  ios_base::sync_with_stdio(NULL);
  cin.tie(NULL);
  cout.tie(NULL);
}
string s[maxn];
map<string, long long> mm;
int main() {
  boost();
  cin >> n >> k >> m;
  for (long long i = 1; i <= n; i++) {
    cin >> s[i];
  }
  for (long long i = 1; i <= n; i++) {
    cin >> a[i];
    mm[s[i]] = a[i];
  }
  for (int i = 1; i <= k; ++i) {
    long long x = 0, mn = INF, xx[maxn];
    cin >> x;
    for (long long j = 1; j <= x; j++) {
      cin >> xx[j];
      mn = min(mn, mm[s[xx[j]]]);
    }
    for (long long j = 1; j <= x; j++) {
      mm[s[xx[j]]] = min(mn, mm[s[xx[j]]]);
    }
  }
  long long ans = 0;
  string t;
  for (int i = 1; i <= m; ++i) {
    cin >> t;
    ans += mm[t];
  }
  cout << ans;
  return 0;
}
