using System;

public class Program

{

    public static void Main()

    {

           int i;

           int j;

           int numOfStudent=0;

           int grade;

           int maxGrade=0;

           int biggestGrade=0;

          for(i=1; i<=30; i++)

              {

                  Console.WriteLine("please enter student number");

                 numOfStudent=int.Parse(Console.ReadLine());

                 for( j=1; j<=numOfStudent; j++)

                     {

                        Console.WriteLine("Please enter grades;");

                        maxGrade=0;

                        grade=int.Parse(Console.ReadLine());

                         if(maxGrade<grade)

                               {

                                  maxGrade=grade;

                               }

                         if(biggestGrade<maxGrade)

                                    {

                                      biggestGrade=maxGrade;

                                    }

                       }

                   Console.WriteLine("The maximum grade of the class is");

                   Console.WriteLine(maxGrade); 

               }

              Console.WriteLine("The biggest grade of all student is");

              Console.WriteLine(biggestGrade);          

   }

}