三行代码实现快速排序

/// <summary>
        /// 快速排序函数
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="list"></param>
        /// <returns></returns>
        IEnumerable<T> QuickSorting<T>(IEnumerable<T> list) where T : IComparable<T>
        {
            if (list.Count() <= 1) return list;

            var pivot = list.First();

            return QuickSorting(list.Where(x => x.CompareTo(pivot) < 0))
                           .Concat(list.Where(x => x.CompareTo(pivot) == 0))
                           .Concat(QuickSorting(list.Where(x => x.CompareTo(pivot) > 0)));

        }

测试：

 static void Main(string[] args)
        {
            List<int> ints = new List<int>
            {
                22,33,11,43,55,123,452,1,3,5,15,153,10000,532,553,22,33,11,53,11,33
            };
            List<int> lists = new Program().QuickSorting<int>(ints).ToList<int>();

            lists.ForEach(A => Console.WriteLine(A));
        }

文章出自：http://www.cnblogs.com/tianmaicheng/archive/2011/08/26/2154756.html