using System;
class StudentGrade
{public static void Main()
 {Console.Write("输入学生百分制的成绩:");
    int Grade=(int)Console.Read();
    switch (Grade/10)
    {case 9:
     case 10:Console.WriteLine("你的成绩为:A");
            break;
     case 8:Console.WriteLine("你的成绩为:B");
            break;
     case 7:Console.WriteLine("你的成绩为:C");
            break;
     case 6:Console.WriteLine("你的成绩为:D");
            break;
     default:Console.WriteLine("你的成绩为:E");
            break;
    }
  }
 }