#if __INCLUDE_LEVEL__ == 0

#include __BASE_FILE__

void Solve() {
  using ld = long double;
#define double ld
  fesetround(FE_UPWARD);
  int n;
  double A, B;
  IN(n, A, B);
  double pA = 1;
  double pB = 1;
  double C = 1;
  vector<double> v;
  for (int i : Rep1(0, n)) {
    double K;
    IN(K);
    C /= i + 1;
    pA *= A;
    pB *= B;
    v.push_back(K * C * pB);
    v.push_back(K * C * -pA);
  }
  double ans = 0;
  ranges::stable_sort(v, {}, LAMBDA(x, abs(x)));
  for (double e : v) {
    ans += e;
  }
  OUT(floor(ans));
#undef double
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  Solve();
}

#elif __INCLUDE_LEVEL__ == 1

#include <bits/stdc++.h>

template <class T> concept MyRange = std::ranges::range<T> && !std::convertible_to<T, std::string_view>;
template <class T> concept MyTuple = std::__is_tuple_like<T>::value && !MyRange<T>;

namespace std {

istream& operator>>(istream& is, MyRange auto&& r) {
  for (auto&& e : r) is >> e;
  return is;
}
istream& operator>>(istream& is, MyTuple auto&& t) {
  apply([&](auto&... xs) { (is >> ... >> xs); }, t);
  return is;
}

ostream& operator<<(ostream& os, MyRange auto&& r) {
  auto sep = "";
  for (auto&& e : r) os << exchange(sep, " ") << e;
  return os;
}
ostream& operator<<(ostream& os, MyTuple auto&& t) {
  auto sep = "";
  apply([&](auto&... xs) { ((os << exchange(sep, " ") << xs), ...); }, t);
  return os;
}

}  // namespace std

using namespace std;

#define LAMBDA(x, ...) ([&](auto&& x) -> decltype(auto) { return __VA_ARGS__; })
#define Rep(...) [](int l, int r) { return views::iota(min(l, r), r); }(__VA_ARGS__)
#define Rep1(...) [](int l, int r) { return Rep(l, r + 1); }(__VA_ARGS__)
#define IN(...) (cin >> forward_as_tuple(__VA_ARGS__))
#define OUT(...) (cout << forward_as_tuple(__VA_ARGS__) << '\n')

#endif  // __INCLUDE_LEVEL__ == 1