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

    ng,ok = -1,1000000000
    while ok-ng > 1:
        mid = (ok+ng)>>1
        a = A
        h = list(map(lambda x: (x-mid)*-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)
        if s <= y*b:
            ok = mid
        else:
            ng = mid
    print(ok)
main()