如何创建一个接受 2 个数字并返回正确计算的计算器程序？（python）[关闭]

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Create a calculator program that:

• takes two numbers and a symbol as parameters
• and returns the correct calculation (The returned value must then be saved)
• as a variable outside of the function and then prints

#I have no clue what a parameter is 
number1 = input("1st number")
number2 = input("2nd number")
#how do you do a list to choose the symbol from e.g like *, +, -, /, MOD, DIV
#i dont know what the rest of the instructions mean

Answer 1

In a comment, I recommended searching existing answers. However, the ones I looked at do not do either of the following: use existing functions in the operator module; map the input operator string to a function with a dict. Perhaps both are too advanced for beginners given such assignments, but they are important to learn.

from operator import add, sub, mul, truediv

operations = {'+':add, '-':sub, '*':mul, '/':truediv}

def calculate(num1, num2, op):
    return operations[op](num1, num2)

print('2 + 3: ', calculate(2, 3, '+'))
print('2 - 3: ', calculate(2, 3, '-'))
print('2 * 3: ', calculate(2, 3, '*'))
print('2 / 3: ', calculate(2, 3, '/'))

Answer 2

I would use a bunch of if statements for this project.

Here is how I would do it:

def calculate(number1, number2, operator)
    result = 0

    if operator == '+':
        result = number1 + number2
    elif operator == '-':
        result = number1 - number2
    elif operator == '*':
        result = number1 + number2
    elif operator == '/':
        result = number1 / number2
    else:
        return 'Wrong input!'
    return result


a = int(input('First number: '))
o = input('Operator: ')
b = int(input('Second number: '))

print(calculate(a, b, o))