N = int(input())
D = list(map(int, input().split()))
a, b = map(int, input().split())
x = max(abs(a), abs(b))
if x in D:
    print(1)
elif x == 0:
    print(0)
else:
    d = max(D)
    print(max(2, (x + d - 1)//d))