求两个多变行是否相交。里面用到了线段是否相交函数，希望对大家有用。-Seek whether the intersection of two changeable. Whether it used the segment intersection function, useful for all of us hope.

对任意多边形进行切割，求其相交部分,相交部分用红色线段标出。-draw two polygon and then they can cut each other.The color of intersected parts are red.

在二维平面下，输入两条线段的始末坐标，并判断该两条线段是否相交-In the two-dimension plane,input begin and end positions of two line segments, then judge two of them have the same point