#include <bits/stdc++.h>
using namespace std;
inline int in() {
  int x, y;
  y = scanf("%d", &x);
  return x;
}
const int MAXN = -1;
int main() {
  int a = in();
  int b = min(in(), in());
  int d = in();
  int p = in(), q = in();
  int x = min(a, d), y = min(b, d);
  cout << max(x * p + max(0, min(b, d - x)) * q,
              y * q + max(0, min(a, d - y)) * p)
       << endl;
  return 0;
}
