#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <tuple>
#include <cmath>
#include <numeric>
#include <functional>
#include <cassert>

#define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl;
#define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl;

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; }

using namespace std;
typedef long long ll;

template<typename T>
vector<vector<T>> vec2d(int n, int m, T v){
    return vector<vector<T>>(n, vector<T>(m, v));
}

template<typename T>
vector<vector<vector<T>>> vec3d(int n, int m, int k, T v){
    return vector<vector<vector<T>>>(n, vector<vector<T>>(m, vector<T>(k, v)));
}

template<typename T>
void print_vector(vector<T> v, char delimiter=' '){
    if(v.empty()) {
        cout << endl;
        return;
    }
    for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter;
    cout << v.back() << endl;
}

using P = pair<ll, int>;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    int n; cin >> n;
    ll a, b, x, y; cin >> a >> b >> x >> y;
    vector<ll> w(n);
    for(int i = 0; i < n; i++) {
        cin >> w[i];
    }
    auto ok = [&](ll p, int a){
        vector<ll> h(n);
        priority_queue<P> que;
        for(int i = 0; i < n; i++){
            h[i] = max(0ll, w[i]-p);
        }
        for(int i = 0; i < n; i++) {
            que.push(P(h[i], i));
        }
        while(a > 0 && !que.empty()){
            auto [_, i] = que.top(); que.pop();
            a--;
            h[i] -= x;
            if(h[i] <= 0) continue;
            que.push(P(h[i], i));
        }
        for(int i = 0; i < n; i++){
            if(h[i] <= 0) h[i] = 0;
        }
        ll sum = accumulate(h.begin(),  h.end(), 0ll);
        return sum <= y*b;
    };
    if(ok(0, a)){
        cout << 0 << endl;
        return 0;
    }
    ll h_max = *max_element(w.begin(), w.end());
    ll l = 0, r = h_max;
    while(r-l > 1){
        ll x = (l+r)/2;
        if(ok(x, a)) r = x;
        else l = x;
    }
    cout << r << endl;
}