#include <bits/stdc++.h>
using namespace std;
int main() {
  long long a, b, c, d, i, j, summ = 0, summ2 = 0, bus[1009], tro[1009], m, n;
  cin >> a >> b >> c >> d >> n >> m;
  for (i = 0; i < n; i++) {
    cin >> bus[i];
  }
  for (i = 0; i < m; i++) {
    cin >> tro[i];
  }
  for (i = 0; i < n; i++) {
    bus[i] = bus[i] * a;
  }
  for (i = 0; i < n; i++) {
    if (bus[i] > b) bus[i] = b;
    summ += bus[i];
  }
  if (summ > c) summ = c;
  for (i = 0; i < m; i++) {
    tro[i] = tro[i] * a;
  }
  for (i = 0; i < m; i++) {
    if (tro[i] > b) tro[i] = b;
    summ2 += tro[i];
  }
  if (summ2 > c) summ2 = c;
  summ = summ + summ2;
  if (summ > d) summ = d;
  cout << summ << endl;
  return 0;
}
