#include <bits/stdc++.h>
using namespace std;
int n, m;
int c1, c2, c3, c4;
int a[1005];
int b[1005];
void Read() {
  cin >> c1 >> c2 >> c3 >> c4;
  cin >> n >> m;
  int i;
  for (i = 1; i <= n; i++) cin >> a[i];
  for (i = 1; i <= m; i++) cin >> b[i];
}
int Rez(int a[], int n) {
  int i;
  int s, p;
  s = 0;
  for (i = 1; i <= n; i++) {
    p = a[i] * c1;
    s += (p > c2) ? c2 : p;
  }
  if (s > c3) return c3;
  return s;
}
void Solve() {
  int TRL;
  int BUS;
  TRL = Rez(a, n);
  BUS = Rez(b, m);
  if (TRL + BUS > c4)
    cout << c4 << "\n";
  else
    cout << TRL + BUS << "\n";
}
int main() {
  Read();
  Solve();
}
