using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace app
{
    class Program
    {
   
         static void Main(string[] args)
        {
            int[] arr = Insert(10); //待排序數組
            DateTime beforDT = System.DateTime.Now;

            Sort(arr, 
 
0, arr.Length - 1);  //調用快速排序函數。傳值(要排序數組，基準值位置，數組長度)
        
             DateTime afterDT = System.DateTime.Now;
            TimeSpan ts = afterDT.Subtract(beforDT);
            Console.WriteLine("DateTime總共花費{0}ms.", ts.TotalMilliseconds);


            Console.ReadKey();
        }
        static int
 
[] Insert(int count)
        {
            Random r1 = new Random();
            int i = 0;
            int[] arr = new int[count];
            while (i < count)
            {
                int a = r1.Next(10, 100000);
                arr[i] = a;
                i++;
            }
            return arr;
        }
        
 
private static void Sort(int[] numbers, int left, int right)
        {
            //左邊索引小於右邊，則還未排序完成 　　
            if (left < right)
            {
                //取中間的元素作為比較基準，小於他的往左邊移，大於他的往右邊移 　　
                int middle = numbers[(left + right) / 2];
                int i = left - 1;
                int j = right + 1;
                while (true)
                {
                    while (numbers[++i] < middle && i < right) ;
                    while (numbers[--j] > middle && j > 0) ;
                    if (i >= j)
                        break;
                    Swap(numbers, i, j);

                }
                Sort(numbers, left, i - 1);
                Sort(numbers, j + 1, right);
            }
        }
        private static void Swap(int[] numbers, int i, int j)
        {
            int number = numbers[i];
            numbers[i] = numbers[j];
            numbers[j] = number;
        }
    }
    }
        
    

C#快速排序