#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c, d, e, f;
  cin >> a;
  cin >> b;
  cin >> c;
  cin >> d;
  cin >> e;
  cin >> f;
  int cost = 0;
  int num1, num2;
  if (f > e) {
    num1 = min(c, min(b, d));
    num2 = min(d - num1, a);
    cout << num2 * e + num1 * f << endl;
  } else {
    num1 = min(d, a);
    num2 = min(d - num1, min(b, c));
    cout << num2 * f + num1 * e << endl;
  }
}
