python制作简单软件

def add(a, b):
    return a + b

def subtract(a, b):
    return a - b

def multiply(a, b):
    return a * b

def divide(a, b):
    return a / b

while True:
    operation = input("Enter operation (+, -, *, /): ")
    if operation not in ['+', '-', '*', '/']:
        print("Invalid operation")
        continue
    num1 = float(input("Enter first number: "))
    num2 = float(input("Enter second number: "))
    result = None
    if operation == '+':
        result = add(num1, num2)
    elif operation == '-':
        result = subtract(num1, num2)
    elif operation == '*':
        result = multiply(num1, num2)
    elif operation == '/':
        if num2 == 0:
            print("Cannot divide by zero")
        else:
            result = divide(num1, num2)
    if result is not None:
        print("Result:", result)
    choice = input("Continue? (y/n): ")
    if choice == 'n':
        break