n = int(input())

m_list = [i for i in map(int, input().strip().split())]
x_list = [i for i in map(int, input().strip().split())]

status = []
for i in range(n): # n种
    temp = []
    for j in range(x_list[i]+1): # 每种多少个
        temp.append(j * m_list[i])
    status.append(temp)

w_0 = set(status[0])
for i in range(1, n):
    w_i = set()
    for j in w_0:
        for k in status[i]:
            w_i.add(j+k)
    w_0 |= w_i
    i += 1

print(len(w_0))