from heapq import heapify,heappush,heappop
n,A,b,x,y = map(int,input().split())
H = list(map(int,input().split()))

def solve(k):
    a = A
    h = list(map(lambda x: (x-k)*-1,H))
    heapify(h)
    while a:
        v = heappop(h)*-1
        if v <= 0:
            break
        heappush(h,(v-x)*-1)
        a -= 1
    s = 0
    while h:
        s += max(0, heappop(h)*-1)
    return s <= y*b

ng,ok = -1,1234567890
while ok-ng > 1:
    mid = (ok+ng)//2
    if solve(mid):
        ok = mid
    else:
        ng = mid
print(ok)