1、按下列要求编程：定义一个描述矩形的类Rectangle,包括的数据成员有宽（width）和长（length）,并实现

class Recangle{private:int width;int length;public:Recangle(){width = 0; length = 0;};Recangle(int w,int h){width = w; height = h;};int circumference(){return 2*(width+height)};int Area(){return width * height};void changeRec(int w,int h){width = w; height = h;};};