#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  vector<int> c(4);
  for (int i = 0; i < 4; i++) cin >> c[i];
  int N = 0, M = 0, ns, ms;
  cin >> ns >> ms;
  vector<int> n(ns), m(ms);
  for (int i = 0; i < ns; i++) {
    cin >> n[i];
    n[i] = min(n[i] * c[0], c[1]);
    N += n[i];
  }
  for (int i = 0; i < ms; i++) {
    cin >> m[i];
    m[i] = min(m[i] * c[0], c[1]);
    M += m[i];
  }
  N = min(N, c[2]);
  M = min(M, c[2]);
  cout << min(N + M, c[3]) << endl;
  return 0;
}
