剑指Offer——快速排序

快排过程： 

代码如下： 

public class QuickSort {
    private int partition(int[] nums, int left, int right) {
        //获取随机基准数
        int random = rangeRandom(left, right);
        //小于基准数的边界
        int small = left-1;
        //将基准数放到最后一位
        swap(nums,random,right);
        for (int i = left;ileft){
            quickSort(nums, left, partitionIndex-1);
        }
        if(partitionIndex