#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
signed main() {
  int a, b, c, d, e, f;
  cin >> a >> b >> c >> d >> e >> f;
  int ans = 0;
  if (e >= f) {
    int dec = min(a, d);
    a -= dec;
    d -= dec;
    ans += dec * e;
    ans += min(min(b, c), d) * f;
  } else {
    int dec = min(min(b, c), d);
    b -= dec, c -= dec, d -= dec;
    ans += dec * f;
    ans += min(a, d) * e;
  }
  cout << ans << '\n';
  return 0;
}
