import sys

# sys.setrecursionlimit(200005)
int1 = lambda x: int(x)-1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = 18446744073709551615
inf = 4294967295
md = 10**9+7
# md = 998244353

from heapq import *

n, a, b, x, y = LI()
hh = LI()

def ok():
    hp = []
    for h in hh:
        if h-m > 0: heappush(hp, -h+m)

    for _ in range(a):
        if not hp: break
        h = -heappop(hp)
        h -= x
        if h > 0: heappush(hp, -h)

    s = -sum(hp)
    # print(s,hp)

    return s <= y*b

l, r = 0, 10**9+1
while l+1 < r:
    m = (l+r)//2
    if ok(): r = m
    else: l = m

print(r)