Compeleted the Student class (and Bonus).

src/CourseRegistrationStarter/RegistrationSystem.java

@@ -10,14 +10,7 @@ public class RegistrationSystem {
     }
 
     public void addCourseToSystem(Course c) {
-        Scanner scanner = new Scanner(System.in);
+        courses.add(c);
-
-        String courseName = scanner.next();
-        String courseCode = scanner.next();
-        int capacity = scanner.nextInt();
-
-        Course newCourse = new Course(courseName, courseCode, capacity);
-        courses.add(newCourse);
     }
 
     public Course findCourseByCode(String code) {

src/CourseRegistrationStarter/Student.java

@@ -21,18 +21,30 @@ public class Student {
     }
 
     public boolean addCourse(Course c) {
-
+        if ((registeredCourses.size() < 3)&&(!(registeredCourses.contains(c))&&(c.getCapacity() > 0))) {
-        return false;
+            registeredCourses.add(c);
+        }
+        else if (registeredCourses.size() >= 3)
+            System.out.println("You can only attend 3 courses!");
+        else if (registeredCourses.contains(c))
+            System.out.println("You can't register twice!");
+        return c.reduceCapacity();
     }
 
     public boolean dropCourse(Course c) {
-        // TODO: Remove the course from the student's list
+        registeredCourses.remove(c);
-        // Restore the course capacity if removal was successful
+        int temp = c.getCapacity();
-        // Return true if the course was dropped, otherwise false
+        c.increaseCapacity();
+        if ((temp > c.getCapacity())&&(!(registeredCourses.contains(c))))
+            return true;
         return false;
     }
 
     public void showRegisteredCourses() {
-        // TODO: Print all registered courses
+        for (Course i : registeredCourses)
+        {
+            System.out.println(i.getCourseName());
+            System.out.println(i.getCourseCode());
+        }
     }
 }