Question

Requirements:

1.     The number of students to enter will be dynamic, minimum of 5.

2.     Ask the user for a student's:

a.     first name

b.     last name

c.      student ID

d.     4 exam grades (each out of 100 points)

Calculate the student's:

e.     final letter grade.

3.     For each student, if the user enters invalid data he will be allowed to enter it again.

4.     Letter grade calculation will use the standard grading scale.

a.     90% - 100% = A

b.     80% - 89% = B

c.      70% - 79% = C

d.     60% - 69% = D

e.     Below 60% = F

5.     The output will consist of:

a.     A list of students who passed (C or higher)

b.     A list of students who did not pass (D or lower)

c.      The person(s) with the highest grade (points, not letter)

 

Restrictions:

1.     main() will only consist of variable declarations, method calls, and small amounts of logic, if necessary.  The majority of the logic will reside in the core methods.

2.     The exam grades must be stored as an array, not 4 separate variables.

3.     User-defined methods must be used for data input, grade calculation, and data output, at a minimum.

OUTPUT:

 

-------------

PASS

----

Aberdeen, Joe        A

Blake, Kevin         A

Garry, Glen          C

Jenakovski, Mary     B

 

FAIL

----

Zoolander, Derek     F

 

HIGHEST GRADE

----

Blake, Kevin         A

Answer 1

// Importing Scanner class to take input.

import java.util.Scanner;

 

// StudentGrades  class starts.

class StudentGrades{

 

        // Instance variables for taking input and storing values.

        String firstName, lastName;

        int studentID;

        int examGrades[] = new int[4];

        char finalLetterGrade;

        float percentage = 0.0f;

         

        // inputDetails() methods to take input from the user.

        public void inputDetails(){

                // Instantiating Scanner class to take input.

                Scanner scanner = new Scanner(System.in);

 

                // Taking input of the First Name.

                System.out.print("Enter First Name : ");

                this.firstName = scanner.nextLine();

 

                // Taking input of the Last Name.

                System.out.print("Enter Last Name : ");

                this.lastName = scanner.nextLine();

 

                // Taking input of the Student ID.

                System.out.print("Enter Student ID : ");

                this.studentID = scanner.nextInt();

                 

                // Taking input of Grades of student in 4 exams.

                System.out.println("Enter Grades of 4 Exams (Out of 100) : ");

                 

                for(int i = 0; i < 4; i++ ){

                        System.out.print("Enter  Grade "+ (i+1) +" : ");

                        this.examGrades[i] = scanner.nextInt(); 

                }

        }

 

        // calculatePercentage() methods to calculate the obtained percentage of the student.

        public void  calculatePercentage(){

                //Calculating percentage.

                for(int i = 0; i < 4; i++ ){

                        this.percentage += this.examGrades[i];  

                }

 

                this.percentage = ( (percentage/400) * 100);

        }

 

        // calculateFinalLetterGrade() methods to calculate the obtained Final Letter Grade of the student.

        public void calculateFinalLetterGrade(){

 

                // Calculating Final Letter Grade and storing it into instance variable of the object.

                if(this.percentage >= 90 && this.percentage <= 100){

                        this.finalLetterGrade = 'A';

                }

                else if(this.percentage >= 80 && this.percentage <= 89){

                        this.finalLetterGrade = 'B';

                }

                else if(this.percentage >= 70 && this.percentage <= 79){

                        this.finalLetterGrade = 'C';

                }

                else if(this.percentage >= 60 && this.percentage <= 69){

                        this.finalLetterGrade = 'D';

                }

                else{

                        this.finalLetterGrade = 'F';

                }

        }

 

        // outputDetails() method to print the output according to Final Grade as mention in the question.

        public static void outputDetails(StudentGrades studentGrades[], int numberOfStudents){

 

                // Local Variable to get the Highest Grade.

                float highestGrade = studentGrades[0].percentage;

                int highestGradeIndex = 0;

 

                System.out.println("-------------------------------------------");

                // Printing details of all the passed students.

                System.out.println("\nPASS");

                System.out.println("----");

 

                for(int i = 0; i < numberOfStudents; i++){

                        if(studentGrades[i].percentage >= 70 ){

                                System.out.println(studentGrades[i].firstName +" "+ studentGrades[i].lastName +" "+ studentGrades[i].finalLetterGrade);

                        }

                }

 

                // Printing details of all the failed students.

                System.out.println("\nFAIL");

                System.out.println("----");

 

                for(int i = 0; i < numberOfStudents; i++){

                        if(studentGrades[i].finalLetterGrade == 'F' ){

                                System.out.println(studentGrades[i].firstName +" "+ studentGrades[i].lastName +" "+ studentGrades[i].finalLetterGrade);

                        }

                }

 

                // Printing details of students who obtained the highest Marks/Percentage or Points.

                System.out.println("\nHIGHEST GRADE");

                System.out.println("----");

 

                // Calculating which student obtained heighest marks.

                for(int i = 1; i < numberOfStudents; i++){

                        if( studentGrades[i].percentage > highestGrade ){

                                highestGrade = studentGrades[i].percentage;

                                highestGradeIndex = i;

                        }

                }

                // Printing the details of student who got Highest Marks.

                System.out.println(studentGrades[highestGradeIndex].firstName +" "+ studentGrades[highestGradeIndex].lastName +" "+ studentGrades[highestGradeIndex].finalLetterGrade);

 

                System.out.println("-------------------------------------------");

        }

 

        //main() method ot the driver method.

        public static void main(String[] args) {

                // Instantiating Scanner class to take input.

                Scanner scanner = new Scanner(System.in);

                // Variable for taking input of number of students.

                int numberOfStudents;

 

                // Taking student of number of Student.

                System.out.print("Enter the number of students (minimum 5) : ");

                numberOfStudents = scanner.nextInt();

 

                // Instantiating Array of StudentGrades class of size as entered by the user.

                StudentGrades studentGrades[] = new StudentGrades[numberOfStudents];

                 

                // Taking Input details, Calculating percentage  and Calculating the Grade for each student.

                for(int i = 0; i < numberOfStudents; i++ ){

                        System.out.println("\n\nEnter details of "+ (i+1) +" student : ");

 

                        //Instantiating StudentGrades object for every student.

                        studentGrades[i] = new StudentGrades();

                        //Calling inputDetails() method for taking input.

                        studentGrades[i].inputDetails();

 

                        //Calling calculatePercentage() method for calculating Percentage of student.

                        studentGrades[i].calculatePercentage();

 

                        //Calling calculateFinalLetterGrade() method for calculating Grade of student.

                        studentGrades[i].calculateFinalLetterGrade();

                }

 

                // Calling outputDetails() method for printing details of all the student as mentions in the question.

                outputDetails(studentGrades, numberOfStudents);

 

        // End of Main method.

        }

// StudentGrades  class Ends.

}