Lesson 1.14

CSA Unit 1.14

Popcorn Hack #1

// Work by [Your Name Here]

public class Dog {
    private String name;
    private String breed;

    public Dog(String name, String breed) {
        this.name = name;
        this.breed = breed;
    }

    public void introduce() {
        System.out.println("My dog " + name + " is a " + breed + "!");
    }
}

// To use it:
public class DogDemo {
    public static void main(String[] args) {
        Dog d = new Dog("Buddy", "Golden Retriever");
        d.introduce();
    }
}

My dog Buddy is a Golden Retriever!

Popcorn Hack 2

public class Counter {
    private int count;

    public void add(int x) {
        count += x;
    }

    public void subtract(int x) {
        count -= x;
    }

    public void multiply(int x) {
        count *= x;
    }

    public void divide(int x) {
        if (x != 0) {
            count /= x;
        } else {
            System.out.println("Cannot divide by zero!");
        }
    }

    public int getCount() {
        return count;
    }

    public static void main(String[] args) {
        Counter c = new Counter();

        c.add(10);        // count = 10
        c.subtract(2);    // count = 8
        c.multiply(3);    // count = 24
        c.divide(4);      // count = 6

        System.out.println("Final count: " + c.getCount());
    }
}

Counter value: 6

Homework Hack

import java.util.ArrayList;
import java.util.Collections;

public class StudentGradeTracker {
    private String name;
    private ArrayList<Integer> grades;

    public StudentGradeTracker(String name) {
        this.name = name;
        this.grades = new ArrayList<>();
    }

    // Adds a grade with error checking
    public void addGrade(int points) {
        if (points < 0 || points > 100) {
            System.out.println("Error: Invalid grade. Must be between 0 and 100.");
            return;
        }
        grades.add(points);
        System.out.println("Adding grade: " + points + " points");
    }

    public double getAverage() {
        if (grades.isEmpty()) return 0.0;
        int total = 0;
        for (int g : grades) total += g;
        return (double) total / grades.size();
    }

    public String getLetterGrade() {
        double avg = getAverage();
        if (avg >= 90) return "A";
        else if (avg >= 80) return "B";
        else if (avg >= 70) return "C";
        else if (avg >= 60) return "D";
        else return "F";
    }

    public int getHighestGrade() {
        if (grades.isEmpty()) return 0;
        return Collections.max(grades);
    }

    public int getLowestGrade() {
        if (grades.isEmpty()) return 0;
        return Collections.min(grades);
    }

    public void dropLowestGrade() {
        if (!grades.isEmpty()) {
            int lowest = getLowestGrade();
            grades.remove(Integer.valueOf(lowest));
            System.out.println("Dropped lowest grade: " + lowest);
        }
    }

    public void reset() {
        grades.clear();
        System.out.println("All grades have been reset for " + name + ".");
    }

    public int compareTo(StudentGradeTracker other) {
        return Double.compare(this.getAverage(), other.getAverage());
    }

    public void printReport() {
        System.out.println("Student Name: " + name);
        System.out.println("Grades: " + grades);
        System.out.printf("Average: %.2f\n", getAverage());
        System.out.println("Highest Grade: " + getHighestGrade());
        System.out.println("Lowest Grade: " + getLowestGrade());
        System.out.println("Letter Grade: " + getLetterGrade());
        System.out.println();
    }

    public static void main(String[] args) {
        System.out.println("=== Student Grade Tracker (Bonus Version) ===\n");

        StudentGradeTracker emma = new StudentGradeTracker("Emma Rodriguez");
        emma.addGrade(95);
        emma.addGrade(88);
        emma.addGrade(92);
        emma.addGrade(85);
        emma.printReport();

        emma.dropLowestGrade();
        System.out.println("--- After Dropping Lowest Grade ---");
        emma.printReport();

        StudentGradeTracker james = new StudentGradeTracker("James Wilson");
        james.addGrade(78);
        james.addGrade(82);
        james.addGrade(75);
        james.printReport();

        int comparison = emma.compareTo(james);
        if (comparison > 0)
            System.out.println(emma.name + " has a higher average than " + james.name);
        else if (comparison < 0)
            System.out.println(james.name + " has a higher average than " + emma.name);
        else
            System.out.println("Both students have the same average!");

        emma.reset();
        emma.printReport();
    }
}

=== Student Grade Tracker (Bonus Version) ===

Adding grade: 95 points
Adding grade: 88 points
Adding grade: 92 points
Adding grade: 85 points
Student Name: Emma Rodriguez
Grades: [95, 88, 92, 85]
Average: 90.00
Highest Grade: 95
Lowest Grade: 85
Letter Grade: A

Dropped lowest grade: 85
--- After Dropping Lowest Grade ---
Student Name: Emma Rodriguez
Grades: [95, 88, 92]
Average: 91.67
Highest Grade: 95
Lowest Grade: 88
Letter Grade: A

Adding grade: 78 points
Adding grade: 82 points
Adding grade: 75 points
Student Name: James Wilson
Grades: [78, 82, 75]
Average: 78.33
Highest Grade: 82
Lowest Grade: 75
Letter Grade: C

Emma Rodriguez has a higher average than James Wilson
All grades have been reset for Emma Rodriguez.
Student Name: Emma Rodriguez
Grades: []
Average: 0.00
Highest Grade: 0
Lowest Grade: 0
Letter Grade: F

Self-Grade

Category	Score	Comment
Functionality	39/40	My program runs perfectly and calculates averages and grades correctly for both students.
Method Implementation	29/30	I implemented all required methods and used instance variables properly.
Code Quality	18/20	Code is well-organized and uses clear variable names. I could add more comments next time.
Output & Presentation	9/10	Output is neatly formatted and matches the example provided.

Final Score: 95/100

Image Proof (Link to issue)

https://github.com/shriya1401/shriyap_2025/issues/14