题解 | #称砝码#

n_weights = int(input())
weights = [int(w) for w in input().split()]
nums = [int(i) for i in input().split()]

# credits to wfj
def count_different_weights(n, weight_lst, count_lst):
    exist_weights = {0}
    for w, c in zip(weight_lst, count_lst):
        need_try_to_add_one = exist_weights
        for i in range(c):
            need_try_to_add_more = []
            for wi in need_try_to_add_one:
                wi += w
                if wi not in exist_weights:
                    need_try_to_add_more.append(wi)
            need_try_to_add_one = need_try_to_add_more
            exist_weights.update(need_try_to_add_one)
    return len(exist_weights)

result = count_different_weights(n_weights, weights, nums)
print(result)