import java.util.Scanner;

public class Students
{
    public static void main (String [] args)
    {
        String[] student;
        String name;
        double courseWork, exam, average;
        char grade;
        int i;

        Scanner keyboard= new Scanner (System.in);
        System.out.println("Please enter names of 10 students: ");
        student= new String[10];

        //Array, prints out student1 - student10 by calling the print method
        for(i=0; i<10; i++)
        {
            System.out.print("Student"  +(i+1)+ ": ");
            student[i] = keyboard.nextLine();
        }
        print(student);

        //Entering data for each student
        do  {
            boolean found;                                          //Making the program re-run
            do  {

                System.out.print("\n");
                System.out.print("Please enter student name: ");
                name = keyboard.nextLine();
                for(int j=0; j<10; j++)
                {
                    if  (name.compareTo(student[j]) == 0)
                    {found = true;
                    }
                    else
                        found = false;
                        System.out.print("Student " +name+ " not found.");
                }
            }   while (found = false);

            if(name.equals("NONE"))                     //Program termination if "NONE" is entered
            {
                System.out.print("Program Terminated...");
                System.exit(0);
            }

            do  {                                       //Keeping values in range (0-100 marks)
                System.out.print("Please enter " +name+ "'s course work mark: ");
                courseWork = keyboard.nextDouble();
                if  (courseWork < 0 || courseWork > 100)
                    System.out.print("Not in valid range, please re-enter");
            }   while (courseWork < 0 || courseWork > 100);

            do  {
                System.out.print("Please enter " +name+ "'s exam mark: ");
                exam = keyboard.nextDouble();
                if  (exam < 0 || exam > 100)
                    System.out.print("Not in valid range, please re-enter");
            }   while (exam < 0 || exam > 100);

            grade = getGrade(exam, courseWork); //Calling the getGrade method
            System.out.print("Grade: " +grade);
            keyboard.nextLine();
        }   while (grade == 'A' || grade == 'B' || grade == 'C' || grade == 'D' || grade == 'F');
    }


    //The print method, used to print the array of students in the main method
    public static void print(String[] student)
    {
        System.out.print("\n");
        System.out.println("List of students you entered are as follows:");
        for(int k=0; k<10; k++)
        {   System.out.println("Student" +(k+1)+ ": " + student[k]);
        }
    }


    //The getGrade method, used to output the grade for each student
    public static char getGrade( double exam, double courseWork )
    {
        double average;
        average = (courseWork + exam) / 2;
        if(average < 50)
        {   return 'F';
        }
        else if(average < 60)
        {   return 'D';
        }
        else if(average < 70)
        {   return 'C';
        }
        else if(average < 80)
        {   return 'B';
        }
        else
        {   return 'A';
        }
    }
}