#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll=long long;
using Graph=vector<vector<pair<int,ll>>>;
#define INF 1000000000000000000
#define MOD 998244353
#define MAX 200000

int main(){
  int N;
  ll A,B,X,Y;
  cin>>N>>A>>B>>X>>Y;
  vector<ll> H(N);
  for(int i=0;i<N;i++){
    cin>>H[i];
  }

  {
    ll x=0;
    vector<ll> h(N);
    for(int i=0;i<N;i++){
      h[i]=max<ll>(0,H[i]-x);
    }
    ll a=A;
    for(int i=0;i<N;i++){
      ll cnt=min<ll>(h[i]/X,a);
      a-=cnt;
      h[i]-=cnt*X;
    }
    sort(h.begin(),h.end());
    ll sum=0;
    for(int i=0;i<N-(int)a;i++){
      sum+=h[i];
    }
    if(sum<=B*Y){
      cout<<0<<'\n';
      return 0;
    }
  }

  ll left=0;
  ll right=1000000000;
  while(left+1<right){
    ll x=(left+right)/2;
    vector<ll> h(N);
    for(int i=0;i<N;i++){
      h[i]=max<ll>(0,H[i]-x);
    }
    ll a=A;
    for(int i=0;i<N;i++){
      ll cnt=min<ll>(h[i]/X,a);
      a-=cnt;
      h[i]-=cnt*X;
    }
    sort(h.begin(),h.end());
    ll sum=0;
    for(int i=0;i<N-(int)a;i++){
      sum+=h[i];
    }
    if(sum<=B*Y){
      right=x;
    }else{
      left=x;
    }
  }
  cout<<right<<'\n';
}