java实现快速排序

import java.util.Random;

public class QuickSorting {

 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  int a[]=new int[20];
  for(int i=0;i<a.length;i++){
   a[i]=new Random().nextInt(100);
  }
 // int a[]={72,12,96,59,67,59,33,55,23,44};
 // int a[]={44,12,23,59,67,59,33,55};
  
  printArray("Before Quick Sorting:",a);
  quickSorting(a,0,a.length-1);
  printArray("After Quick Sorting:",a);
 }

 private static void quickSorting(int[] a, int low, int high) {
  int temp=partition(a,low,high);
  if((temp-1)-low>=1){
  quickSorting(a,low,temp-1);
  }
  if((high-(temp+1))>=1){
  quickSorting(a,temp+1,high);
  }
 }
 public static int partition(int[] a,int low,int high){
  int pivot=a[low];
  while(low<high){
   while(low<high&&a[high]>=pivot) high--;
   swap(a,low,high);
   while(low<high&&a[low]<=pivot) low++;
   swap(a,low,high);
  }
  return low;
 }
 private static void swap(int[] a,int low,int high) {
  int temp=a[low];
  a[low]=a[high];
  a[high]=temp;
 }

 private static void printArray(String string, int[] a) {
  System.out.println();
  System.out.print(string);
  for(int i=0;i<a.length;i++){
   System.out.print(a[i]+" ");
  }
 }
}