class Shape:
    def area(self):
        return 0
class Circle(Shape):
    def __init__(self,name,r):
        self.name = name
        self.r = r
    def area(self):
        return (3.14*self.r*self.r)
class Square(Shape):
    def __init__(self,name,side):
        self.name = name
        self.side = side
    def area(self):
        return (self.side*self.side)

shape_list = []
circle_1 = Circle("circle_1",1)
square_1 = Square("square_1",1)
shape_list.append(circle_1)
shape_list.append(square_1)
for shape in shape_list:
    print(f"{shape.name}的面积:{shape.area()}")