python 创建分数类

# encoding:utf-8

# 求最大公约数的函数,有待优化...
def gmc(a, b):
    for x in range(min(a, b), 1, -1):
        if a % x == 0 and b % x == 0:
            return x


class Fraction:
    def __init__(self, top, bottom):
        self.top = top
        self.bottom = bottom
        
	# 打印属性
    def __repr__(self):
        return f'(class {__class__.__name__}) {self.top}/{self.bottom}'
	
	# 加法属性
    def __add__(self, other):
        if isinstance(other,Fraction):
            top = self.top *other.bottom + other.top * self.bottom
            bottom = self.bottom * other.bottom
            gcd = gmc(top,bottom)
            return Fraction(top//gcd,bottom//gcd)
        else:
            return ValueError,'必须为Fraction类!'


if __name__ == '__main__':
    a = Fraction(1, 4)
    b = Fraction(1, 2)
    print(a+b)