#include <bits/stdc++.h>
using namespace std;
int c1, c2, c3, c4, n, m;
void solve() {
  cin >> c1 >> c2 >> c3 >> c4;
  cin >> n >> m;
  int ans = 0, temp = 0;
  for (int i = 0; i < n; i++) {
    int a;
    cin >> a;
    if (a * c1 > c2)
      temp += c2;
    else
      temp += a * c1;
  }
  if (temp > c3) temp = c3;
  ans = temp;
  temp = 0;
  for (int i = 0; i < m; i++) {
    int a;
    cin >> a;
    if (a * c1 > c2)
      temp += c2;
    else
      temp += a * c1;
  }
  if (temp > c3) temp = c3;
  ans += temp;
  if (ans > c4) ans = c4;
  cout << ans << endl;
}
int main() {
  solve();
  return 0;
}
