#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <deque>
#include <forward_list>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iostream>
#include <limits>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;
using lint = long long;
using pint = pair<int, int>;
using plint = pair<lint, lint>;
struct fast_ios {
    fast_ios() { cin.tie(nullptr), ios::sync_with_stdio(false), cout << fixed << setprecision(20); };
} fast_ios_;
#define ALL(x) (x).begin(), (x).end()
#define FOR(i, begin, end) for (int i = (begin), i##_end_ = (end); i < i##_end_; i++)
#define IFOR(i, begin, end) for (int i = (end)-1, i##_begin_ = (begin); i >= i##_begin_; i--)
#define REP(i, n) FOR(i, 0, n)
#define IREP(i, n) IFOR(i, 0, n)
template <typename T, typename V> void ndarray(vector<T> &vec, const V &val, int len) { vec.assign(len, val); }
template <typename T, typename V, typename... Args> void ndarray(vector<T> &vec, const V &val, int len, Args... args) {
    vec.resize(len), for_each(begin(vec), end(vec), [&](T &v) { ndarray(v, val, args...); });
}
template <typename T> bool chmax(T &m, const T q) { return m < q ? (m = q, true) : false; }
template <typename T> bool chmin(T &m, const T q) { return m > q ? (m = q, true) : false; }
int floor_lg(long long x) { return x <= 0 ? -1 : 63 - __builtin_clzll(x); }
template <typename T1, typename T2> pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first + r.first, l.second + r.second); }
template <typename T1, typename T2> pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first - r.first, l.second - r.second); }
template <typename T> vector<T> sort_unique(vector<T> vec) {
    sort(vec.begin(), vec.end()), vec.erase(unique(vec.begin(), vec.end()), vec.end());
    return vec;
}
template <typename T> int arglb(const std::vector<T> &v, const T &x) { return std::distance(v.begin(), std::lower_bound(v.begin(), v.end(), x)); }
template <typename T> int argub(const std::vector<T> &v, const T &x) { return std::distance(v.begin(), std::upper_bound(v.begin(), v.end(), x)); }
template <typename T> istream &operator>>(istream &is, vector<T> &vec) {
    for (auto &v : vec) is >> v;
    return is;
}
template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
    os << '[';
    for (auto v : vec) os << v << ',';
    os << ']';
    return os;
}
template <typename T, size_t sz> ostream &operator<<(ostream &os, const array<T, sz> &arr) {
    os << '[';
    for (auto v : arr) os << v << ',';
    os << ']';
    return os;
}
#if __cplusplus >= 201703L
template <typename... T> istream &operator>>(istream &is, tuple<T...> &tpl) {
    std::apply([&is](auto &&...args) { ((is >> args), ...); }, tpl);
    return is;
}
template <typename... T> ostream &operator<<(ostream &os, const tuple<T...> &tpl) {
    os << '(';
    std::apply([&os](auto &&...args) { ((os << args << ','), ...); }, tpl);
    return os << ')';
}
#endif
template <typename T> ostream &operator<<(ostream &os, const deque<T> &vec) {
    os << "deq[";
    for (auto v : vec) os << v << ',';
    os << ']';
    return os;
}
template <typename T> ostream &operator<<(ostream &os, const set<T> &vec) {
    os << '{';
    for (auto v : vec) os << v << ',';
    os << '}';
    return os;
}
template <typename T, typename TH> ostream &operator<<(ostream &os, const unordered_set<T, TH> &vec) {
    os << '{';
    for (auto v : vec) os << v << ',';
    os << '}';
    return os;
}
template <typename T> ostream &operator<<(ostream &os, const multiset<T> &vec) {
    os << '{';
    for (auto v : vec) os << v << ',';
    os << '}';
    return os;
}
template <typename T> ostream &operator<<(ostream &os, const unordered_multiset<T> &vec) {
    os << '{';
    for (auto v : vec) os << v << ',';
    os << '}';
    return os;
}
template <typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &pa) {
    os << '(' << pa.first << ',' << pa.second << ')';
    return os;
}
template <typename TK, typename TV> ostream &operator<<(ostream &os, const map<TK, TV> &mp) {
    os << '{';
    for (auto v : mp) os << v.first << "=>" << v.second << ',';
    os << '}';
    return os;
}
template <typename TK, typename TV, typename TH> ostream &operator<<(ostream &os, const unordered_map<TK, TV, TH> &mp) {
    os << '{';
    for (auto v : mp) os << v.first << "=>" << v.second << ',';
    os << '}';
    return os;
}
#ifdef HITONANODE_LOCAL
const string COLOR_RESET = "\033[0m", BRIGHT_GREEN = "\033[1;32m", BRIGHT_RED = "\033[1;31m", BRIGHT_CYAN = "\033[1;36m", NORMAL_CROSSED = "\033[0;9;37m", RED_BACKGROUND = "\033[1;41m", NORMAL_FAINT = "\033[0;2m";
#define dbg(x) cerr << BRIGHT_CYAN << #x << COLOR_RESET << " = " << (x) << NORMAL_FAINT << " (L" << __LINE__ << ") " << __FILE__ << COLOR_RESET << endl
#define dbgif(cond, x) ((cond) ? cerr << BRIGHT_CYAN << #x << COLOR_RESET << " = " << (x) << NORMAL_FAINT << " (L" << __LINE__ << ") " << __FILE__ << COLOR_RESET << endl : cerr)
#else
#define dbg(x) (x)
#define dbgif(cond, x) 0
#endif

int main() {
    int N;
    cin >> N;
    lint A, B, X, Y;
    cin >> A >> B >> X >> Y;
    vector<int> Hv(N);
    cin >> Hv;
    dbg(Hv);

    auto solve = [&](lint k) -> bool {
        priority_queue<lint> H;
        for (auto h : Hv) {
            if (h > k) H.push(h - k);
        }
        REP(t, A) {
            if (H.empty()) break;
            lint h = H.top();
            H.pop();
            h -= X;
            if (h > 0) H.push(h);
        }
        lint sum = 0;
        while (H.size()) {
            int h = H.top();
            H.pop();
            sum += h;
        }
        return sum <= lint(B * Y);
    };

    lint lo = -1, hi = 1LL << 30;
    while (hi - lo > 1) {
        lint k = (hi + lo) / 2;
        (solve(k) ? hi : lo) = k;
    }
    cout << hi << '\n';
}