开放的银行问题，似乎无法弄清楚为什么我的解决方案没有通过最后一个测试用例

Question

我想在DoSelect平台上解决一个问题。

以下是问题陈述

作为开发人员，Sid希望为Open项目做出贡献。他希望为存款、提款、增加利息以及对银行账户(在某些情况下)使用银行手续费创造功能。

此外，这类帐户的一个限制因素是，如果操作导致帐户余额为负数，则帐户余额将被重新初始化为100。例如，如果当前余额为40，您想提取60，那么由于40-60是负的，在此操作后，现在帐户有100。

因为他认为自己是一个聪明的程序员，他想为所有这些任务创建一个单一的功能。函数是"Transaction“，最多有两个参数"a”和"b“。它根据给定的参数执行不同的任务。但是Sid对OOP的概念一无所知。

class Account:
      function init (variable balance):
          //init is the standerd python __init__(self, variables) method. 
          //it initializes the account with user given balance 
          member variable balance= balance 
 
      function transaction (variable a, variable b):
          //a (if given) denotes the amount to be withdraw/deposit in the account. 
              //so add a to balance if a is positive, otherwise subtract (-a) from balance if a is negative.
          //b (if given) denotes the interest rate to give/charge to the account based on its sign.
              //so add b% of current balance (rounded to nearest integer) to the balance as an interest, if b is positive 
          //otherwise subtract (-b)% of currenct balance (rounded to nearest integer) to the balance as bank charge, if b is negative
          //after each operation, take care that, any time balance goes to negative, make it as 100. 
 
          //if neither a nor b is given:
              //do nothing
          //if a is given but b is not given:
              //add/subtract a to the balance, based on sign of a
          //if a is not given and b is given:
              //add/subtract b% of current balance to the balance, based on sign of b
          //if both a and b are given:
              //first add/subtract a to the balance, get the new balance, then add/subtract b% of the new balance to the new balance.
          //everytime take care that, if balance goes to negative, reinitialize it with 100.

以下是我所做的

class Account:
    
    def __init__(self, balance):
        self.balance = balance
        #self.balance = 100
    
    def transaction(self, a = 0, b = 0):
        if a != 0 and b != 0:
            self.balance += a
            self.balance += round((self.balance) * (b / 100))
            if self.balance < 0:
                self.balance = 100
        elif a != 0 and b == 0:
            self.balance += a
            if self.balance < 0:
                self.balance = 100
        elif a==0 and b != 0:
            self.balance += round((self.balance) * (b / 100))
            if self.balance < 0:
                self.balance = 100
        else:
            pass
        return self.balance
    
    def get_balance(self):
        return self.balance

当我在平台上验证时，它成功地验证了测试用例。然而，当我尝试提交它时，它在一个测试用例上失败了。DoSelect平台没有显示他们用来验证的测试用例，所以我找不到它。

Answer 1

正如我在评论中所说：Account(0).transaction(-1, 10)为100提供了解决方案。任务说，每当余额变为负值时，就将其重新初始化为100。如果将此规则应用于每一步，则结果应该是110 (0 -> -1 -> 100 -> 110)。

我不认为a和b需要不同的if-组合。这是开发人员必须将需求转换为有意义的代码的时刻。并且不需要get_balance方法，您可以直接访问该属性。

class Account:
    def __init__(self, balance):
        self.balance = balance
        if self.balance < 0:
            self.balance = 100

    def transaction(self, a=0, b=0):
        self.balance += a
        if self.balance < 0:
            self.balance = 100
        self.balance += round(self.balance * (b / 100))
        if self.balance < 0:
            self.balance = 100


account = Account(0)
account.transaction(-1, 10)
print(account.balance)

一个“普通”的程序员会创建一个处理if self.balance < 0的方法，但是由于Sid不知道OOP的概念，所以我只是重复了代码。使用OOP，该类的代码可以是：

class Account:
    def __init__(self, balance):
        self.balance = balance
        self.adjust_balance()

    def adjust_balance(self):
        if self.balance < 0:
            self.balance = 100

    def transaction(self, a=0, b=0):
        self.balance += a
        self.adjust_balance()
        self.balance += round(self.balance * (b / 100))
        self.adjust_balance()

有了更多的经验，程序员可能会使用属性来实现平衡。

class Account:
    def __init__(self, balance):
        self._balance = balance

    @property
    def balance(self):
        return self._balance

    @balance.setter
    def balance(self, value):
        self._balance = value
        if self._balance < 0:
            self._balance = 100

    def transaction(self, a=0, b=0):
        self.balance += a
        self.balance += round(self.balance * (b / 100))