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)