using System;

public class Program

{

    public static void Main()   

    { 

        const int numOfCourses = 4;

        int[] unitGP;

        string[] myCourse;

        int[] units;

        int[] scores;

        // Create and initialize the arrays' dimensions

        unitGP = new int[numOfCourses];

        myCourse = new string[numOfCourses];

        units = new int[numOfCourses];

        scores = new int[numOfCourses];

        //Enter course details

        for (int idx = 0; idx < numOfCourses; idx++)

        {

            Console.Write($"Enter Course {idx+1}: ");

            myCourse[idx] = Console.ReadLine();

            Console.WriteLine("Enter course unit: ");

            units[idx] = int.Parse(Console.ReadLine());

            Console.WriteLine("Enter Exam Score: ");

            scores[idx] = int.Parse(Console.ReadLine());

            unitGP[idx] = GetGrade(scores[idx]) * units[idx];

        }

        int TotalUnit = 0;

        double TotalGradePoint = 0.0;

        int TotalScore = 0;

        for (int idx = 0; idx < numOfCourses; idx++)

        {

            TotalScore += scores[idx];

            TotalUnit += units[idx];

            TotalGradePoint += unitGP[idx];

        }

        double GPA = TotalGradePoint / TotalUnit;

        Console.WriteLine($"Total Score: {TotalScore}");

        Console.WriteLine($"Total Units: {TotalUnit}");

        Console.WriteLine("Student GPA = {0}" , GPA);

        if (GPA <= 1.50)

        {

         Console.WriteLine("Fail");

        }

        else if (GPA <= 2.49)

        {

         Console.WriteLine("Third class");

        }

        else if (GPA <= 3.49)

        {

         Console.WriteLine("Second Class Lower");

        }

        else if (GPA <= 4.49)

        {

         Console.WriteLine("Second Class Upper");

        }

        else

        {

         Console.WriteLine("First Class");

        }

    }

    private static int GetGrade(int score)

    {

        int grade = 0;

        if (score <= 39)

            grade = 0;

        else if( score <= 45)

            grade = 1;

        else if( score <= 49)

         grade = 2;

​

        else if( score <= 59)

          grade = 3;

        else if( score <= 69)

            grade = 4;

        else

            grade = 5;

        return grade;

    }

}