Python基本计算器程序不返回答案

Question

所以我想弄清楚如何使用我在python中学到的东西来制作计算器,但我无法让它给我一个答案.

这是我到目前为止的代码:

def add(x, y):
    return x + y

def subtract (x, y):
    return x - y


def divide (x, y):
    return x / y


def multiply (x, y):
    return x / y


print("What calculation would you like to make?")
print("Add")
print("Subtract")
print("Divide")
print("Multiply")


choice = input("Enter choice (add/subtract/divide/multiply)\n")


num1 = float(input("Enter first number: "))
num2 = float(input("Enter second number: "))        

if choice == ("add, Add"):
    print(add(num1,num2))

elif choice == ("subtract, Subtract"):
    print(subtract(num1,num2))

elif choice == ("divide, Divide"):
    print(divide(num1,num2))

elif choice == ("multiply, Multiply"):
    print(multiply(num1,num2))`

Answer 1

代替:

choice == ("add, Add")

你要:

choice in ["add", "Add"]

或者更有可能:

choice.lower() == "add"

为什么？您试图检查选择输入是否等于代码中的元组("添加,添加"),这不是您想要的.您想要检查选择输入是否在列表中["添加","添加"].或者,处理此输入的更好方法是将输入小写并将其与所需的字符串进行比较.