Console.WriteLine("输入人数"); int n = Convert.ToInt32(Console.ReadLine()); ArrayList chengji = new ArrayList();//建成绩集合 for (int i = 0; i < n; i++) { Console.WriteLine("请输入成绩"); chengji.Add( Convert.ToInt32(Console.ReadLine()));//把输入的成绩放到成绩集合里 } int sum=0; foreach (int a in chengji) { sum = sum + a; } Console.WriteLine("总分是"+sum); int avg = sum / n; Console.WriteLine("平均分是"+avg);