#include <bits/stdc++.h>
int main() {
  int n, m, c1, c2, c3, c4, d, s1, s2, s3, s4, i;
  scanf("%d%d%d%d%d%d", &c1, &c2, &c3, &c4, &n, &m);
  s1 = 0;
  s2 = 0;
  s3 = 0;
  s4 = 0;
  for (i = 0; i < n; i++) {
    scanf("%d", &d);
    if (d * c1 > c2)
      s1 += c2;
    else
      s1 += d * c1;
  }
  if (s1 > c3) s1 = c3;
  for (i = 0; i < m; i++) {
    scanf("%d", &d);
    if (d * c1 > c2)
      s2 += c2;
    else
      s2 += d * c1;
  }
  if (s2 > c3) s2 = c3;
  s3 = s2 + s1;
  if (c4 < s3) s3 = c4;
  printf("%d\n", s3);
  return 0;
}
