#include <bits/stdc++.h>
    using namespace std;
    #include <math.h>
    #include <iomanip>
    #include <cstdint>
    #include <string>
    #include <sstream>
    template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
    template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
    #define rep(i,n) for (int i = 0; i < (n); ++i)
    typedef long long ll;
    typedef long double ld;
    typedef unsigned long long ull;
    using P=pair<ll,ll>;
    const ll INF=1001001001;
    const int mod=1e9+7;

    void solve(){
        ll n,a,b,x,y;
        cin>>n>>a>>b>>x>>y;
        vector<ll>h(n);
        rep(i,n)cin>>h[i];
        
        auto f=[&](int k){
            priority_queue<int>q;
            rep(i,n){
                if(h[i]-k<=0){continue;}
                q.push(h[i]-k);
            }
            rep(i,a){
                if(q.empty()){break;}
                int p=q.top();q.pop();
                p-=x;
                if(p>0){q.push(p);}
            }
            ll sum=0;
            while(!q.empty()){
                int p=q.top();q.pop();
                sum+=p;
            }
            return sum<=b*y;
        };
        
        int l=-1,r=1e9+5;
        while(r-l>1){
            int mid=(l+r)/2;
            if(f(mid)){r=mid;}
            else{l=mid;}
        }
        cout<<r<<endl;
    }  

    int main(){
        ios_base::sync_with_stdio(false);
        cin.tie(NULL);
        
        solve(); 

        return 0;
    }