java算法 --快速排序

package Solve;

import java.util.Scanner;


public class Solve
{
	static Scanner scan = new Scanner(System.in);
	 public static void main(String[] args)
	{
		int[] num = { 100,40,60,87,34,11,56,0};
		qsort(num,0,num.length - 1);
		for (int x:num)
		{
			System.out.print(x + "\t");
		}
	}
	 
	 static void qsort(int[] arr,int b,int e)
	 {
		 int x = arr[(b + e) / 2];
		 int i = b,j = e;
		 while ( i < j)  //一趟
		 {
			 while ( arr[i] < x)
				 i++;
			 while ( arr[j] > x)
				 j--;
			 if ( i < j) //!
			 {
				 int t = arr[i];
				 arr[i] = arr[j];
				 arr[j] = t;
				 i++;j--; //!
			 }
		 }
     
		 if ( i < e)  //分治
			 qsort(arr,b,i);
		 if ( j > b) //分治
			 qsort(arr,b,j);
	 }
}