题解 | #汽水瓶#

递归解法

num_list = []

while True:
    nums = input()
    if nums == '0':
        break
    else:
        num_list.append(int(nums))


class Hand(object):
    def __init__(self):
        self.res_list = []

    def handler(self, num):
        if num >= 3:
            consult = num // 3  # 商
            remainder = num % 3  # 余数
            new_num = consult + remainder
            if new_num == 2:
                new_num += 1
            self.res_list.append(consult)
            self.handler(new_num)
        else:
            self.res_list.append(0)


def run():
    for n in num_list:
        app = Hand()
        app.handler(n)
        print(sum(app.res_list))


run()