题解 | #称砝码#

kind = int(input())
ms = list(map(int, input().split()))
xs = list(map(int, input().split()))

dp = [{0} for _ in range(kind + 1)]  # dp[i]表示第i种及其之前的重量和
for i in range(1, kind + 1):
    for j in range(xs[i - 1] + 1):
        for val in dp[i - 1]:
            val = val + j * ms[i - 1]
            dp[i].add(val)
print(len(dp[kind]))