#include <bits/stdc++.h>
using namespace std;
signed main() {
  long long Aprice, Bprice;
  long long Akg, Bkg[10010];
  long long n;
  long long kg;
  long long price;
  cin >> n;
  cin >> Aprice >> Bprice;
  cin >> Akg;
  price = Aprice;
  kg = Akg;
  for (long long i = 0; i < n; i++) {
    cin >> Bkg[i];
  }
  sort(Bkg, Bkg + n, greater<long long>());
  for (long long i = 0; i < Bprice; i++) {
    kg += Bkg[i];
  }
  for (long long i = 0; i < Bprice; i++) {
    price += Bprice;
  }
  cout << kg / price << endl;
  return 0;
}
