#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define ALL(v) v.begin(),v.end()
typedef long long ll;
 
#include<bits/stdc++.h>
using namespace std;

ll n,aa,b,x,y;
ll A[100100];
bool f(ll k){
  ll a=aa;
  vector<ll> H(n);
  rep(i,n) H[i]=A[i]-k;
  
  sort(ALL(H));
  reverse(ALL(H));
  int now=0;
  while(a>0 && now<n && H[now]>=x){
    H[now]-=x;
    a--;
    if(H[now]<x) now++;
  }
  sort(ALL(H));
  reverse(ALL(H));
  now=0;
  while(a>0 && now<n){
    H[now]-=x;
    a--;
    now++;
  }
  if(now==n){
    return true;
  }
  ll sum=0;
  rep(i,n){
    if(H[i]>0) sum+=H[i];
  }
  if(sum<=b*y) return true;
  else return false;
}

 
int main(){
  ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
  
  cin>>n>>aa>>b>>x>>y;
  rep(i,n) cin>>A[i];
  
  ll ng=-1,ok=1e9+7;
  while(ok-ng>1){
    ll mid=(ok+ng)/2;
    if(f(mid)) ok=mid;
    else ng=mid;
  }
  cout<<ok<<endl;
  
  return 0;
}