点集凸包Gram扫描法 c++程序-point set convex hull Gram scanning procedures c

gram法求凸包， 凸包是区域内任意两点的直线不与边界相交的简单闭区域。 gram算法能够高效地求解出凸包的点集-gram Method convex hull, convex hull is a straight line between any two points within the region do not intersect with the boundary simple closed area. gram algorithm can efficiently solve