说明：  扫描线种子填充算法 本程序实现区域填充功能，首先输入多边形顶点的个数,回车， 然后依次输入各顶点的坐标格式如下：100,123回车 一定要在中间用逗号隔开噢，输完最后一个点后，屏幕上会依次 画出各条边，最后填充满. 程序还不完善，比如颜色值应该用变量表示以易于修改，画多边形和求种子点 应该做成独立的函数等等，以后再做上吧，这是细节的问题
(Scan line seed fill algorithm in this program area filling function, first of all, enter the number of polygon vertices, carriage return, to be followed by enter the coordinates of the vertex format is as follows: Enter 100123 in the middle must be separated by commas Oh, lose the last one point, the screen will in turn draw the edges, and finally full filling. program is not perfect, such as the color value variable that should be used to easily modify, and demand painting polygon seed point should be made independent of the function and so on, later做上it, this is the problem details)