查找数组里相同元素的个数

 int[] list = new int[] { 1,1,2,3,1,2,4,3,3,2,4,5,6,5,6,7,3,2,8};
            Dictionary<int, int> dic = new Dictionary<int, int>();
            foreach (int item in list)
            {
                if (!dic.ContainsKey(item))
                {
                    dic[item] = 1;
                }
                else
                {
                    dic[item]++;
                }
            }

            foreach (var item in dic)
            {
                Console.WriteLine(item.Key+":有{0}个",item.Value);
            }
            Console.ReadKey();