Using the 2D arrays in java, you are required to calculate the grade of 5 students for 5 courses. For every student, input the marks for each course from keyboard and display the respective earned grade of the student. (Perform necessary calculations)

Here's the program to solve the problem as described:

Source Code..

package oop.solutions;

 //@author Java_Programs

import java.util.Scanner;

public class 2D_Array

{

     public static void main(String[] args)

    {

       Scanner sc = new Scanner(System.in);

       Grade g = new Grade();

       

       g.inputMarks();

       g.calculate_Percentage();

       g.printMarks();

       g.printGrade();

    }

}

//Taking another class for calculation(for good practice)

class Grade

{

       Scanner sc = new Scanner(System.in);

    

       int total_studs = 5, total_courses = 5;

       float [][] marks = new float[total_studs][total_courses];

       float [] obtainedMarks = new float[total_studs];

       float [] percentage = new float[total_studs];

public void inputMarks()

        {

           for(int row=0; row<total_studs; row++)

                {

                    System.out.println("\nEnter marks for student "+(row+1)+": ");

                    for(int col=0; col<total_courses; col++)

                    {

                            System.out.println("Enter marks for course "+(col+1)+": ");

                            marks[row][col] = sc.nextFloat();

                            obtainedMarks[row]= obtainedMarks[row]+marks[row][col];

                    }

}

}

        public void calculate_Percentage()

        {          

            for(int row=0; row<total_studs; row++)

                {

                  obtainedMarks[row]=0;

                  

                  for(int col=0; col<total_courses; col++)

                    {                          

                            obtainedMarks[row]= obtainedMarks[row]+marks[row][col];

                            percentage[row] = (( obtainedMarks[row]/(100*total_courses) )*100);

                    }

                }

        }

        

public void printMarks()

        {

for(int row=0; row<total_studs; row++)

                {

  System.out.println("\nStudent "+(row+1)+" marks: ");

  for(int col=0; col<total_courses; col++)

                  {

System.out.println("Marks of course "+(col+1)+": " +marks[row][col]);

                        

          }

                  System.out.println("Total Obtained Marks: "+obtainedMarks[row]);

                  System.out.println("Percentage: "+percentage[row]);

}

}

public void printGrade()

        {

            for(int row=0; row<total_studs; row++)

            {

                if(percentage[row]>=80)

                {

                    System.out.println("\nStudent "+(row+1)+" Grade: A+");

                }

                else if(percentage[row]>=70 && percentage[row]<=79)

                {

                    System.out.println("\nStudent "+(row+1)+" Grade: A");

                }

                else if(percentage[row]>=60 && percentage[row]<=69)

                {

                    System.out.println("\nStudent "+(row+1)+" Grade: B");

                }

                else if(percentage[row]>=50 && percentage[row]<=59)

                {

                    System.out.println("\nStudent "+(row+1)+" Grade: C");

                }

                else

                {

                    System.out.println("\nStudent "+(row+1)+" Grade: F");

                }

            }

}

}    

Explanation:

The given code is a Java program that takes the marks of five students in five courses using a 2D array and calculates their percentage and grade.

The program uses a Scanner class to take input from the user for the marks of each student in each course. Then, it calculates the total obtained marks and percentage for each student using a for loop and stores them in an array. Finally, it prints the marks, total obtained marks, percentage, and grade for each student using another for loop.

The Grade class is used to encapsulate the data and the methods related to the calculation and printing of the student grades. The main method creates an object of the Grade class and calls its inputMarks, calculate_Percentage, printMarks, and printGrade methods to perform the necessary tasks.

This program demonstrates the use of 2D arrays and for loops to perform calculations and print data. It also showcases the importance of encapsulation and the use of classes for better organization and readability of the code.

In conclusion, this Java program is an example of how to use arrays, loops, and classes to calculate and print student grades based on their marks