分别定义图形类Shape（抽象基类），继承类矩形类Rectangle、正方形类Square、

圆形类Circle；并且计算周长和面积。在另一个main函数中分别创建矩形、 正方形和圆形对象，设置所需的属性值，打印其周长和面积。（备注：只要把该文件解压，把里面的东东COPY去即可使用）-Graphics categories are defined Shape (abstract base class), the succession of quasi-rectangular type Rectangle, square-type Square, round type Circle　and calculate perimeter and area. In another main function to create, respectively, rectangular, square and round objects, set the required attribute value, print the perimeter and area. (Note: As long as the extract of the document to go inside to use the Eastern COPY)