#include <bits/stdc++.h>
using namespace std;
int main() {
  int c1, c2, c3, c4;
  while (cin >> c1 >> c2 >> c3 >> c4) {
    int N, M, i, j, k, Sum = 0, SumT = 0;
    vector<int> Bus, Train;
    cin >> N >> M;
    while (N--) {
      cin >> i;
      Bus.push_back(i);
    }
    while (M--) {
      cin >> i;
      Train.push_back(i);
    }
    Sum = 0;
    for (i = 0; i < Bus.size(); i++) {
      if (Bus[i] * c1 < c2)
        Sum += Bus[i] * c1;
      else
        Sum += c2;
    }
    if (Sum > c3) Sum = c3;
    for (i = 0; i < Train.size(); i++) {
      if (Train[i] * c1 < c2)
        SumT += Train[i] * c1;
      else
        SumT += c2;
    }
    if (SumT > c3) SumT = c3;
    if (SumT + Sum < c4)
      cout << SumT + Sum << endl;
    else
      cout << c4 << endl;
    ;
  }
}
