#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
const int INF = 1e9;
//const long long LINF = 1e18;
//const bool debug = false;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define endl "\n"
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
vector<long long>h;
long long n, a, b;
long long x, y;
bool f(int c) {
	priority_queue<long long>pq;
	rep(i, h.size())if (h[i] - c > 0)pq.push(h[i] - c);
	rep(i, a) {
		if (pq.empty())break;
		long long top = pq.top();
		pq.pop();
		top -= x;
		if (top > 0)pq.push(top);
	}
	long long sum = 0;
	while (!pq.empty()) {
		sum += pq.top();
		pq.pop();
	}
	return sum <= y * b;
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cin >> n >> a >> b;
	cin >> x >> y;
	h.resize(n);
	rep(i, n) cin >> h[i];
	int ng = -1;
	int ok = INF + 1;
	while (1 < abs(ok - ng)) {
		int c = (ng + ok) / 2;
		if (f(c)) ok = c;
		else ng = c;
	}
	cout << ok << endl;
	return 0;
}