快速排序

 private static int sortUnit(int[] array, int low, int high)

        {

            int key = array[low];

            while (low < high)

            {

                /*从后向前搜索比key小的值*/

                while (array[high] >= key && high > low)

                    --high; 

                /*比key小的放左边*/

                array[low] = array[high];   

                /*从前向后搜索比key大的值，比key大的放右边*/

                while (array[low] <= key && high > low)

                    ++low; 

                /*比key大的放右边*/

                array[high] = array[low];

            }

            /*左边都比key小，右边都比key大。//将key放在游标当前位置。//此时low等于high */

            array[low] = key;

            foreach (int i in array)

            {

                Console.Write("{0} ", i);

            }

            Console.WriteLine();

            return high;

        }    

        /**快速排序 

*@paramarry 

*@return */

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

        {

            if (low >= high)

                return; 

            /*完成一次单元排序*/

            int index = sortUnit(array, low, high); 

            /*对左边单元进行排序*/

            sort(array, low, index - 1);

            /*对右边单元进行排序*/

            sort(array, index + 1, high);

        }