#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c, d, e, f;
  cin >> a >> b >> c >> d >> e >> f;
  int s1 = a, s2, min;
  if (b < c) {
    s2 = b;
  } else {
    s2 = c;
  }
  if (s1 < s2) {
    min = s1;
  } else {
    min = s2;
  }
  if (d >= s1 + s2) {
    cout << (s1 * e + s2 * f) << endl;
  } else {
    if (e > f) {
      if (d > s1) {
        cout << s1 * e + (d - s1) * f << endl;
      } else {
        cout << d * e << endl;
      }
    } else {
      if (d > s2) {
        cout << s2 * f + (d - s2) * e << endl;
      } else {
        cout << d * f << endl;
      }
    }
  }
}
