算法课程的快速排序的实现,快速排序的精华在于partition函数的实现，本实现中分别采用了原始的partition和随机化的partition，以便于达所期望的速度。-the implementation for quick sort in the course of alogrithm.The essence of quick sort lies in the implementation of the function partition.The code contains two imlementation methods for partion——the normal one and the randomised one.By compatation, the speed of the randomised one has a better expectation.