#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:5000000000")
const int Inf = 2e9;
long long LINF = (long long)4e18;
using namespace std;
long long mod = 1e9 + 7;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  long long ans = 0;
  vector<double> v(n);
  for (int i = 0; i < n; ++i) {
    cin >> v[i];
  }
  double x, f;
  cin >> x >> f;
  for (int i = 0; i < n; ++i) {
    ans += f * ceil((v[i] - x) / (x + f));
  }
  cout << ans;
  return 0;
}
