C#实现不用随机函数(Random)的洗牌算法

代码不多,先看效果:

类代码:

 1 static class  ShuffleCards
 2 {
 3     private static int lastHash = 0;
 4     public static void Work(byte[] cards)
 5     {
 6         if (lastHash == 0)
 7             lastHash = System.Environment.TickCount;
 8         int len = cards.Length - 2;
 9         int mod = 0;
10         byte temp = 0;
11         for (int i = cards.Length - 1; i >= 0 && len>0; i--)
12         {
13             lastHash = (lastHash << 5) - lastHash + i;
14             mod = lastHash < 0 ? lastHash % len * (-1) : lastHash % len;
15             temp = cards[mod];
16             cards[mod] = cards[i];
17             cards[i] = temp;
18             len--;
19         }
20     }
21 }

测试代码:

 1 //16张牌0~F
 2 byte[] cards = new byte[16];
 3 //洗上99次
 4 for (int j = 0; j < 100; j++)
 5 {
 6     //每次都初始化顺序为 0~F
 7     for (int i = 0; i < cards.Length; i++)
 8         cards[i] = (byte)i;
 9     //洗牌调用
10     ShuffleCards.Work(cards);
11     StringBuilder ret = new StringBuilder();
12     //输出
13     for (int i = 0; i < cards.Length; i++)
14         ret.Append(cards[i].ToString("X") + " ");
15     Console.WriteLine(j.ToString()+" > "+ ret.ToString());
16 }
17 Console.ReadLine();