對List內元素進行全排列

對List中元素進行全排列，使用了遞歸，代碼如下：

class Program     {         static void Main(string[] args)         {             List<int> list = new List<int>() { 6,7,8};             foreach (var p1 in Permutate(list, list.Count))             {                 foreach (var i in p1)                     Console.Write(i.ToString() + " ");                 Console.WriteLine();             }               string strTest = "Cary";             foreach (List<char> p2 in Permutate(strTest.ToCharArray().ToList(), strTest.Length))             {                 string strTmp = new string(p2.ToArray());                 Console.Write(strTmp + " ");             }             Console.WriteLine();                  }           public static void CircleRight(IList seq, int count)         {             object tmp = seq[count - 1];             seq.RemoveAt(count - 1);             seq.Insert(0, tmp);         }           public static IEnumerable<IList> Permutate(IList seq, int count)         {             if (count == 1) yield return seq;             else             {                 for (int i = 0; i < count; i++)                 {                     foreach (var perm in Permutate(seq, count - 1))                         yield return perm;                     CircleRight(seq, count);                 }             }