Scala实现快速排序

代码

1. scala>:paste
2. //Entering paste mode (ctrl-D to finish)
4. def qSort(a:List[Int]):List[Int]=
5. if(a.length<2) a
6. else
7. qSort(a.filter(_<a.head))++
8. a.filter(_ == a.head)++
9. qSort(a.filter(_>a.head))
11. //Exiting paste mode, now interpreting.
13. qSort:(a:List[Int])List[Int]
15. scala> qSort(List(3,1,2))
16. res47:List[Int]=List(1,2,3)
18. scala> qSort(List(3,8,5,31,1,2))
19. res48:List[Int]=List(1,2,3,5,8,31)