运用C#编程语言完成多边形裁剪算法程序。实现输入一个多边和一段线后能够自动将线裁剪并保留多边形内的线段而舍弃多边形外的线段。-Using C# programming language to complete polygon clipping algorithm program. Enter a multilateral and achieve some line after line can automatically crop and retained within the polygon