#include <bits/stdc++.h>
const int NMAX = 200001;
long long v[NMAX];
int main() {
  int n;
  scanf("%d ", &n);
  for (int i = 0; i < n; i++) scanf("%I64d ", &v[i]);
  long long x, f;
  scanf("%I64d %I64d ", &x, &f);
  long long ans = 0;
  for (int i = 0; i < n; i++) {
    long long q = (v[i] + f) / (x + f) + ((v[i] + f) % (x + f) != 0) - 1;
    ans += q;
  }
  printf("%I64d\n", ans * f);
}
