设计一个名为Ellipse表示椭圆的类，其数据成员为圆心坐标和半长轴和半短轴的长度，成员函数包括构造函数、设置数据成员值的函数、计算面积的函数和显示参数的函数。其中构造函数有两个，一个没有参数，将圆心初始化为（0，0）,两个半轴的长度设为0；另一个构造函数设置圆心和两个半轴为指定值。-The design called the Ellipse said the class of elliptical members of its data center coordinates and semi-major axis and semi-minor axis length, member functions, including the constructor, set the value of data member function that computes the function and display function of the parameters of the area. Which the constructor without a parameter, the center will be initialized to (0,0), the length of the two axle set to 0　another constructor to set the center and two axle to the specified value.