如何修复文本计算器中的错误？

Question

我试图制作一个非常简单的文本计算器，但我一直遇到这个问题。这是我的代码：num1 = input("Enter in the first number")num2 = input("Enter in the second number")sign = input("Enter in the calculator operator you would like")elif sign = "+":   print(num1 + num2)elif sign = "-":   print(num1 - num2)elif sign = "*":   print(num1*num2)elif sign = "/":   print(num1/num2)抱歉，我是 python 新手...

Answer 1

您的代码不起作用的原因是因为您只是将两个数字相乘/除/加/减，而这两个数字现在声明为一个字符串。

在 python 中，您不能将字符串作为整数进行加/减/乘/除。您需要将 num1 和 num2 声明为整数。

num1 = int(input("Enter in your first number"))

num2 = int(input("Enter in your second number"))

sign = input("Enter in the calculator operator you would like")

if sign == "+":

   print(num1 + num2)

elif sign == "-":

   print(num1 - num2)

elif sign == "*":

   print(num1*num2)

elif sign =="/":

   print(num1/num2)

Answer 2

您的代码中有很多语法错误，请查看注释以了解可以改进的地方，底部有一些阅读材料！

num1 = int(input("Enter in the first number")) # You need to cast your input to a int, input stores strings.

num2 = int(input("Enter in the second number")) # Same as above, cast as INT

sign = input("Enter in the calculator operator you would like")

# You cannot use `elif` before declaring an `if` statement. Use if first!

if sign == "+": # = will not work, you need to use the == operator to compare values

   print(num1 + num2)

elif sign == "-": # = will not work, you need to use the == operator to compare values

   print(num1 - num2)

elif sign == "*": # = will not work, you need to use the == operator to compare values

   print(num1*num2)

elif sign == "/": # = will not work, you need to use the == operator to compare values

   print(num1/num2)

代码可以很好地适应这些更改，但是您应该阅读Python 语法和运算符！

Answer 3

您收到此错误是因为默认情况下输入会给出一个字符串。在使用它之前，您必须将其转换为 int。

num1 = int(input("Enter in the first number"))

num2 = int(input("Enter in the second number"))

sign = input("Enter in the calculator operator you would like")

if sign == "+":

   print(num1 + num2)

elif sign == "-":

   print(num1 - num2)

elif sign == "*":

   print(num1*num2)

elif sign == "/":

   print(num1/num2)