#include <bits/stdc++.h>
int main() {
  int c1, c2, c3, c4, i, m, n, a[1000], b[1000], suma = 0, sumb = 0, sum;
  scanf(
      "%d"
      "%d"
      "%d"
      "%d"
      "%d"
      "%d",
      &c1, &c2, &c3, &c4, &n, &m);
  for (i = 0; i < n; i++) {
    scanf("%d", &a[i]);
  }
  for (i = 0; i < m; i++) {
    scanf("%d", &b[i]);
  }
  for (i = 0; i < n; i++) {
    if ((a[i] * c1) > c2)
      suma += c2;
    else
      suma += (a[i] * c1);
  }
  for (i = 0; i < m; i++) {
    if ((b[i] * c1) > c2)
      sumb += c2;
    else
      sumb += (b[i] * c1);
  }
  if (suma > c3) suma = c3;
  if (sumb > c3) sumb = c3;
  if ((suma + sumb) > c4)
    sum = c4;
  else
    sum = suma + sumb;
  printf("%d", sum);
  return 0;
}
