ArrayList n = new ArrayList();

            n.Add();//集合中添加元素用Add,分别添加了1，2

            n.Add();

            foreach (int a in n)//用foreach循环语句读取

            {

                Console.WriteLine(a);

            }

ArrayList cj = new ArrayList();

            for (int i = ; i < ; i++)

            {

                Console.WriteLine("请输入第{0}同学的成绩", i + );

                cj.Add(Convert.ToInt32(Console.ReadLine()));

            }

            int sum = ;

            foreach (int a in cj)

            {

                sum = sum + a;

            }

            int avg = sum / cj.Count;

            cj.Sort();

            Console.WriteLine("平均分为：" + avg);

            foreach (int a in cj)

            {

                Console.WriteLine(a);

            }