选择排序:
思想:选择排序的思想也非常简单,就是从一堆数中选出最小值,然后和顶部元素互换,之后再用同样的方法排序剩余的数,最终得到排序的结果。
代码:
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Diagnostics; using System.Net; using System.Threading; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { for (int i = 1; i <= 5; i++) { List<int> list = new List<int>(); //插入2k个随机数到数组中 for (int j = 0; j < 2000; j++) { Thread.Sleep(1); list.Add(new Random((int)DateTime.Now.Ticks).Next(0, 100000)); } Console.WriteLine("\n第" + i + "次比较:"); Stopwatch watch = new Stopwatch(); watch.Start(); var result = list.OrderBy(single => single).ToList();//这里这个single=>single不懂 watch.Stop(); Console.WriteLine("\n系统的快速排序耗费时间:" + watch.ElapsedMilliseconds); Console.WriteLine("输出前是十个数:"+string.Join(",",result.Take(10).ToList())); watch.Start(); result = SelectionSort(list); watch.Stop(); Console.WriteLine("\n选择排序耗费时间:" + watch.ElapsedMilliseconds); Console.WriteLine("输出前是十个数:" + string.Join(",", result.Take(10).ToList())); } Console.ReadLine(); } //快速排序算法 static List<int> SelectionSort(List<int> list) { for (int i = 0; i < list.Count-1; i++) { int tempIndex = i; for (int j = i + 1; j < list.Count; j++) { if (list[tempIndex] > list[j]) tempIndex = j; } int temp = list[i]; list[i] = list[tempIndex]; list[tempIndex] = temp; } return list; } } }
总结:选择排序也是比较容易理解的,非常直观。但是性能不是很好。