计算器函数不输出任何内容

Question

我需要设计一个具有以下UI的计算器：

Welcome to Calculator!
1  Addition
2  Subtraction
3  Multiplication
4  Division
Which operation are you going to use?: 1
How many numbers are you going to use?: 2
Please enter the number: 3
Please enter the number: 1
The answer is 4.

这是我到目前为止所拥有的：

print("Welcome to Calculator!")
class Calculator:
def addition(self,x,y):
added = x + y
return sum
def subtraction(self,x,y):
diff = x - y
return diff
def multiplication(self,x,y):
prod = x * y
return prod
def division(self,x,y):
quo = x / y
return quo

calculator = Calculator()
print("1 tAddition")
print("2 tSubtraction")
print("3 tMultiplication")
print("4 tDivision")
operations = int(input("What operation would you like to use?:  "))
x = int(input("How many numbers would you like to use?:  "))
if operations == 1:
a = 0
sum = 0
while a < x:
number = int(input("Please enter number here:  "))
a += 1
sum = calculator.addition(number,sum)

我真的需要一些帮助！Python 3 中所有关于计算器的教程都比这简单得多(因为它只需要 2 个数字，然后简单地打印出答案(。

我需要帮助使我制作的计算器类中的函数工作。当我尝试运行到目前为止我所拥有的东西时，它让我输入我的数字等等，但随后它就结束了。它不会运行操作或其他任何操作。我知道到目前为止我只有加法，但如果有人能帮我弄清楚加法，我想我可以做剩下的。

Answer 1

原样代码不起作用。在addition函数中，您返回变量sum该变量将与函数中的构建冲突sum该变量。

所以只需返回添加的，并且通常避免sum，使用类似sum_的东西：

这对我来说很好用：

print("Welcome to Calculator!")
class Calculator:
def addition(self,x,y):
added = x + y
return added
def subtraction(self,x,y):
diff = x - y
return diff
def multiplication(self,x,y):
prod = x * y
return prod
def division(self,x,y):
quo = x / y
return quo
calculator = Calculator()
print("1 tAddition")
print("2 tSubtraction")
print("3 tMultiplication")
print("4 tDivision")
operations = int(input("What operation would you like to use?:  "))
x = int(input("How many numbers would you like to use?:  "))
if operations == 1:
a = 0
sum_ = 0
while a < x:
number = int(input("Please enter number here:  "))
a += 1
sum_ = calculator.addition(number,sum_)
print(sum_)

运行：

$ python s.py
Welcome to Calculator!
1   Addition
2   Subtraction
3   Multiplication
4   Division
What operation would you like to use?:  1
How many numbers would you like to use?:  2
Please enter number here:  45
Please enter number here:  45
90

Answer 2

程序接受输入，运行一系列操作，然后结束而不显示结果。 在 while 循环结束后尝试类似print(sum)的操作。