【Python】魔法方法：数据运算

【小甲鱼】【零基础入门学习Python】【魔法方法：数据运算】

 

 订正：divmod(a,b)返回的是一个元组(a//b,a%b)

举例：

>>> class New_int(int):
    def __add__(self,other):
        return int.__sub__(self,other)
    def __sub__(self,other):
        return int.__add__(self,other)

    
>>> a = New_int(3)
>>> b = int(4)
>>> a+b
-1
>>> a-b
7
>>> a = int(3)
>>> a+b
7
>>> a-b
-1
>>> b = New_int(4)
>>> a
3
>>> b
4
>>> a+b
7
>>> a-b
-1
>>> a = New_int(3)
>>> a
3
>>> a+b
-1
>>> a-b
7