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