Question

Java Program:

In this project, you will write a program called GradeCalculator that will calculate the grading statistics of a desired number of students. Your program should start out by prompting the user to enter the number of students in the classroom and the number of exam scores. Your program then prompts for each student’s name and the scores for each exam. The exam scores should be entered as a sequence of numbers separated by blank space. Your program will also check for negative scores. If any score is negative, it will prompt the user to reenter the scores. You do not have to deal with inputs that are not numbers. For each student, calculate the student’s the average score, lowest score, highest score, letter grade, and the number of stars to give the student. Once the letter grade has been calculated, use it to calculate an appropriate number of stars the student will received. The letter grade is computed as followed: 90 to 100 is A, 80 and less than 90 is B, 70 and less than 80 is C, 60 and less than 70 is D, anything less than 60 is F. The number of stars is assigned as followed: A is 4 stars, B is 3 stars, C is 2 stars, D is 1 star, and F is 0 stars (no star). The program then displays the statistics about the student as shown in the sample run. Before the program terminates, it prints the class statistics: average grade, lowest grade, highest. See sample output for format. See sample run to have a better idea of what the program should do. Grading: Your program will be graded on a ten-point scale. Your program is expected to have comments. Try to match your output with the same run. Submission: Upload your solution to assignment 1 in blackboard. Sample Run: Welcome to GradeCalculator!

Please enter the number of students: 2 Please enter the number of exams : 3

---------------------------------------- Enter student 1’s name : Sample Name Enter exam scores : 90 100 -80 Invalid exam scores, reenter: 90 100 80

Grade statistics for Sample Name Average : 90 Letter grade: A Sample Name gets 4 stars! ****

---------------------------------------- Enter student 2’s name: Another Name Enter exam scores: 80 95 70

Grade statistics for Another Name Average : 81.66 Letter grade: C Another Name gets 2 stars! **

---------------------------------------- Class statistics: Average: 85.83 Lowest : 81.66 Highest: 90

Done. Good bye!

Answer 1

import java.util.*;
public class Main
{
public static char getgrade(double score)
{
if(score>=90&&score<=100)
return 'A';
else if(score>=80&&score<90)
return 'B';
else if(score>=70&&score<80)
return 'C';
else if(score>=60&&score<70)
return 'D';
else
return 'F';
}
public static String getstars(char grade)
{
if(grade=='A')
return " gets 4 stars!****";
else if(grade=='B')
return " gets 3 stars!***";
else if(grade=='C')
return " gets 2 stars!**";
else if(grade=='D')
return " gets 1 star!*";
else
return " No Stars for F grade";
}
   public static void main(String[] args)
   {
   int num_students,num_exams;
   String name;
   char letter_grade;
   char class_grade;
   Scanner s = new Scanner(System.in);
       System.out.println("Welcome to GradeCalculator!");
       System.out.println("Please enter the number of students: ");
       num_students=s.nextInt();
       System.out.println("Please enter the number of exams: ");
       num_exams=s.nextInt();
       double score,student_average=0,class_average=0,student_lowest,student_highest,class_lowest=101,class_highest=0;
       for(int i=0;i<num_students;i++)
       {
       student_average=0;
       student_lowest=101;
       student_highest=0;
       System.out.println("Enter student "+(i+1)+"’s name : ");
       name=s.nextLine();
       name=s.nextLine();
       System.out.println("Enter exam scores : ");
       for(int j=0;j<num_exams;j++)
       {
score= s.nextDouble();
while(score<0||score>100)
{
System.out.println("Invalid exam scores, reenter: ");
score= s.nextDouble();
}
if(score<student_lowest)
student_lowest=score;
if(score>student_highest)
student_highest=score;
student_average=student_average+score;
       }
       student_average=student_average/num_exams;
       class_average=class_average+student_average;
       System.out.println("Grade statistics for "+name+" Average: "+student_average+" Student Lowest: "+student_lowest+" Student Highest: "+student_highest+" Letter Grade: "+getgrade(student_average)+" "+name+getstars(getgrade(student_average)));
       if(student_average<class_lowest)
       class_lowest=student_average;
       if(student_average>class_highest)
       class_highest=student_average;
       }
       class_average=class_average/num_students;
       System.out.println("Class statistics: Average: "+class_average+" Lowest: "+class_lowest+" Highest: "+class_highest+" Grade: "+getgrade(class_average)+" Class: "+getstars(getgrade(class_average)));
   }
}