#include <bits/stdc++.h>
using namespace std;
using LL = long long;

template <typename T>
struct Fenwick {
    int n;
    vector<T> a;

    Fenwick(int n) { init(n); }

    void init(int n) {
        this->n = n;
        a.assign(n + 1, 0);
    }

    void modify(int x, T s) {
        for (; x; x -= x & (-x)) {
            a[x] += s;
        }
    }

    T query(T x) {
        T ans = 0;
        for (x; x <= n; x += x & (-x)) {
            ans += a[x];
        }
        return ans;
    }

    T query(int l, int r) { return query(r) - query(l); }
};

void solve() {
    int n, k, m, c, d;
    cin >> n >> k >> m >> c >> d;
    vector<int> a(n + 1);
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    auto p = a;
    sort(p.begin() + 1, p.end());
    Fenwick<int> t(n + 1);
    for (int i = 1; i <= n; i++) {
        int idx = lower_bound(p.begin(), p.end(), a[i]) - p.begin();
        t.modify(idx, 1);
    }

    auto check = [&](LL x) -> bool {
        int mx = 0;
        for (int i = 1; i + m - 1 <= n; i++) {
            int j = i + m - 1;
            int idx = lower_bound(p.begin(), p.end(), x) - p.begin();
            int cnt = t.query(idx);
            for (int x = i; x <= j; x++) {
                if (a[x] + 1LL * d * (x - i) > x) {
                    cnt++;
                }
            }
            mx = max(mx, cnt);
        }
        return mx >= k;
    };

    LL l = 0, r = 1e18;
    while (l < r) {
        LL mid = (l + r + 1) / 2;
        if (check(mid)) {
            l = mid;
        } else {
            r = mid - 1;
        }
    }
    cout << l << "\n";
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}