#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c, d, e, f;
  cin >> a >> b >> c >> d >> e >> f;
  int s = d;
  int mn = min(a, d);
  int sum1 = mn * e;
  d -= mn;
  sum1 += (min(b, min(c, d))) * f;
  mn = min(b, min(c, s));
  int sum2 = mn * f;
  s -= mn;
  sum2 += min(a, s) * e;
  cout << max(sum1, sum2) << endl;
  return 0;
}
