[No000087]Linq排序,SortedList排序,二分法排序性能比较

using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;

namespace ConsoleTest
{

class Program
{
static void Main(string[] args)
{

List<string> listTest = new List<string>();
for (int i = 1; i <= 500000; i++)//50_0000
{
listTest.Add(i.ToString().PadLeft(10, '0'));
}

Stopwatch stopMatch = new Stopwatch();
stopMatch.Start();
List<string> listOrder = listTest.OrderByDescending(c => c).ToList<string>();
stopMatch.Stop();

Console.WriteLine("Linq排序耗时:\t{0}毫秒", stopMatch.ElapsedMilliseconds.ToString());

stopMatch.Reset();

stopMatch.Start();

var sortedList = new System.Collections.Generic.SortedList<string, string>();
foreach (var item in listTest)
{
sortedList.Add(item,item);
}
Console.WriteLine("SortedList排序耗时:\t{0}毫秒", stopMatch.ElapsedMilliseconds.ToString());
stopMatch.Stop();

string[] arrTest = listOrder.ToArray();

stopMatch.Reset();
stopMatch.Start();
QuickSort(arrTest, 0, arrTest.Length - 1);

stopMatch.Stop();

Console.WriteLine("二分法排序耗时:\t{0}毫秒", stopMatch.ElapsedMilliseconds.ToString());

Console.Read();

}

/// <summary>
/// 二分法从小到大排序
/// </summary>
/// <param name="array">需要排序的字符串数组</param>
/// <param name="start">排序元素的起始下标</param>
/// <param name="end">排序元素的结止下标</param>
public static void QuickSort(string[] array, int start, int end)
{

//有可能造成start>end   因为递归调用时j+1，可能引起j比end还大1。 另外如果数组是空的，或者输入错误也会出现这种情况
if (end <= start)
{
return;
}
else
{

//取中间元素为中心点，然后移到最右边
int sign = (start + end) / 2;
string tmp = array[end];
array[end] = array[sign];
array[sign] = tmp;
int j = start;

for (int i = start; i <= end - 1; i++)
{

//小于的元素和标记互换，等于的不能互换，否则会形成死循环
if (array[i].CompareTo(array[end]) == -1)
{

tmp = array[i];
array[i] = array[j];
array[j] = tmp;
j = j + 1;

}

}

//把标记元素和第一个>=它的元素位置互换，这样数组就分成2个部分，一个部分比中心值小，一个部分比中心值大。
tmp = array[j];
array[j] = array[end];
array[end] = tmp;
QuickSort(array, start, j);
QuickSort(array, j + 1, end);
}

}

}
}