Question

如果一个人每月只支付信用卡公司要求的最低月付款，请写一个程序来计算一年后的信用卡余额。

我正在尝试编写一个程序，用于打印一年后支付的最终余额

balance = 4213

annualInterestRate = 0.2

monthlyPaymentRate = 0.04

month = 1

new_balance = (balance - (balance*monthlyPaymentRate))*(1+(annualInterestRate/12))


while month < 13:
    print "Month: " + str(month)
    print "Minimum monthly payment: " + str(round(minimum_monthly_payment, 2))
    print "Remaining balance: " + str(round(new_balance, 2))
    month += 1

我的输出显示了这个：

Month: 1
Minimum monthly payment: 168.52
Remaining balance: 4111.89

Month: 2
Minimum monthly payment: 168.52
Remaining balance: 4111.89

Month: 3
Minimum monthly payment: 168.52
Remaining balance: 4111.89

但我应该得到这样的东西：

Month: 1
Minimum monthly payment: 168.52
Remaining balance: 4111.89

Month: 2
Minimum monthly payment: 164.48
Remaining balance: 4013.2

Month: 3
Minimum monthly payment: 160.53
Remaining balance: 3916.8

Answer 1

你做了3次同一行：new_balance = (balance - (balance*monthlyPaymentRate))*(1+(annualInterestRate/12))

这里没有任何变量，每个while循环后都会更新。您应该更新balance以获得每次较低的数字。

Answer 2

看起来您的值没有更新，因为您忘记每月更新余额！尝试每次循环更新balance变量，如下所示：

while month < 13:
    print "Month: " + str(month)
    print "Minimum monthly payment: " + str(round(minimum_monthly_payment, 2))
    print "Remaining balance: " + str(round(balance, 2))
    balance = (balance - (balance*monthlyPaymentRate))*(1+(annualInterestRate/12))
    month += 1

此外，为了使您的代码更容易阅读（以及更多Pythonic），您可以使用Python的内置列表结构，而不是使用您自己的while循环：

for month in range(1, 13):
    print "Month: %d" % month
    print "Minimum monthly payment: %d" % round(minimum_monthly_payment, 2)
    print "Remaining balance: %d" % round(balance, 2)
    balance = (balance - (balance * monthlyPaymentRate)) * (1 + (annualInterestRate / 12)

Answer 3

您不需要变量new_balance，您只应修改变量balance：

while month < 13:
    print "Month: " + str(month)
    print "Minimum monthly payment: " + str(round(minimum_monthly_payment, 2))
    balance = (balance - (balance*monthlyPaymentRate))*(1+(annualInterestRate/12))
    print "Remaining balance: " + str(round(balance, 2))
    month += 1

<强>输出：

Month: 1
Minimum monthly payment: 168.52
Remaining balance: 4111.89
Month: 2
Minimum monthly payment: 168.52
Remaining balance: 4013.2
Month: 3
Minimum monthly payment: 168.52
Remaining balance: 3916.89
Month: 4
Minimum monthly payment: 168.52
Remaining balance: 3822.88
Month: 5
Minimum monthly payment: 168.52
Remaining balance: 3731.13
Month: 6
Minimum monthly payment: 168.52
Remaining balance: 3641.58
Month: 7
Minimum monthly payment: 168.52
Remaining balance: 3554.19
Month: 8
Minimum monthly payment: 168.52
Remaining balance: 3468.89
Month: 9
Minimum monthly payment: 168.52
Remaining balance: 3385.63
Month: 10
Minimum monthly payment: 168.52
Remaining balance: 3304.38
Month: 11
Minimum monthly payment: 168.52
Remaining balance: 3225.07
Month: 12
Minimum monthly payment: 168.52
Remaining balance: 3147.67

计算信贷余额的计划

3 个答案: