#include <bits/stdc++.h>
using namespace std;
long long ans;
int a, b, c, d, e, f, g;
int main() {
  scanf("%d%d%d%d%d%d", &a, &b, &c, &d, &e, &f);
  if (e > f) ans += min(a, d);
  a -= ans, d -= ans;
  ans *= e;
  g = min(min(b, c), d);
  ans += f * g;
  b -= g, c -= g, d -= g;
  ans += e * min(a, d);
  printf("%lld", ans);
}
