Python计算器异常问题咨询：输入第二个数后仍重复请求输入

你的计算器持续要求输入第二个数字，核心问题出在原代码的qwe()函数逻辑上：

def qwe():
    try:
        global y
        y = int(input("enter second number: "))
    except ValueError:
        print("you don't enter correct")
    qwe()  # 无论输入是否合法，都会再次调用自身，导致无限循环

这段代码中，不管输入是否成功转换为整数，最后都会无条件递归调用qwe()，因此即使输入了正确数字，程序也会陷入无限循环，持续要求输入第二个数字。

修复后的完整代码 #

print("Python Basic Calculator Version 1.12")

print('''
type in the math operation you would like to complete:
+ for addition
- for subtraction
* for multiplication
/ for division
** for power
% for modulo
''')

def main():
    def get_first_num():
        try:
            return int(input("enter first number: "))
        except ValueError:
            print("you don't enter correct")
            return get_first_num()
    
    x = get_first_num()        

    def get_operation():
        ops = ["+","-","*","/","**","%"]
        o = input("type the operation: ")  # 修正拼写错误 opreation -> operation
        if o in ops:
            return o
        else:
            print("you don't enter correct")
            return get_operation()
    
    o = get_operation()

    def get_second_num():
        try:
            return int(input("enter second number: "))
        except ValueError:
            print("you don't enter correct")
            return get_second_num()
    
    y = get_second_num()        

    # 用elif替代多个独立if，提升执行效率
    if o == "+": 
        z = x + y
        print(z)
    elif o == "-":  
        z = x - y
        print(z)
    elif o == "*":
        z = x * y
        print(z)
    elif o == "/":
        z = x / y
        print(z)
    elif o == "**":
        z = x ** y
        print(z)
    elif o == "%":
        z = x % y
        print(z)

main()

主要修改点 #

• 修复输入数字函数的递归逻辑：仅当输入不合法时才递归调用，输入成功则返回数字并终止递归
• 移除全局变量，改用函数返回值传递数据，代码逻辑更清晰
• 修正拼写错误opreation为operation
• 用elif替代多个独立if，减少不必要的条件判断
• 给嵌套函数起更具语义的名称，提升代码可读性

内容的提问来源于stack exchange，提问作者Amar Ashraf