package log;

 public class Test4 {

     /**

      * java算法---快速排序

      *

      * @param args

      */

     public static void main(String[] args) {

         // 需要排序的数组

         int arr[] = { 49, 20, 36, 51, 18, 94, 61, 31, 50 };

         // 循环输出该数组内容

         System.out.println("排序之前：");

         for (int a : arr) {

             System.out.print(a + "\t");

         }

         System.out.println();

         if (arr.length > 0) {

             sort(arr, 0, arr.length - 1);

         }

         // 循环输出该数组内容

         System.out.println("排序之后：");

         for (int a : arr) {

             System.out.print(a + "\t");

         }

         System.out.println();

     }

     public static int getMiddle(int[] list, int low, int high) {

         int temp = list[low];

         while (low < high) {

             while (low < high && list[high] >= temp) {

                 high--;

             }

             list[low] = list[high];

             while (low < high && list[low] <= temp) {

                 low++;

             }

             list[high] = list[low];

         }

         list[low] = temp;

         return low;

     }

     public static void sort(int[] list, int low, int high) {

         if (low < high) {

             int middle = getMiddle(list, low, high);

             sort(list, low, middle - 1);

             sort(list, middle + 1, high);

         }

     }

 }