SoftUniCoursePlanning

    import java.util.Arrays;
    import java.util.List;
    import java.util.Scanner;
    import java.util.stream.Collectors;

    public class SoftUniCoursePlanning {
        public static void main(String[] args) {
            Scanner scanner = new Scanner(System.in);
            List<String> schedule = Arrays.stream(scanner.nextLine().split(", ")).collect(Collectors.toList());

            String input = scanner.nextLine();

            while(!input.equals("course start")) {
                String[] tokens = input.split(":");
                String command = tokens[0];
                String lessonTitle = tokens[1];
                switch(command) {
                    case "Add":
                        //"Add:Databases" -> ["Add", "Databases"]
                        if(!schedule.contains(lessonTitle)) {
                            schedule.add(lessonTitle);
                        }
                        break;
                    case "Insert":
                        //Insert:Arrays:0 -> ["Insert", "Arrays", "0"]
                        int index = Integer.parseInt(tokens[2]);
                        if(!schedule.contains(lessonTitle)) {
                            schedule.add(index, lessonTitle);
                        }
                        break;
                    case "Remove":
                        if(schedule.contains(lessonTitle)) {
                            schedule.remove(lessonTitle);
                        }
                        int indexLesson = schedule.indexOf(lessonTitle);
                        if(schedule.get(indexLesson + 1).equals(lessonTitle+"-Exercise")) {
                            schedule.remove(indexLesson + 1);
                        }
                        break;
                    case "Swap":
                        //Arrays, Lists, Methods, Databases, Databases-Exercise
                        //Swap:Lists:Databases
                        String lessonTitle2 = input.split(":")[2];
                        if (schedule.contains(lessonTitle) && schedule.contains(lessonTitle2)) {
                            int lesson1Index = schedule.indexOf(lessonTitle);
                            int lesson2Index = schedule.indexOf(lessonTitle2);
                            schedule.set(lesson1Index, lessonTitle2);
                            schedule.set(lesson2Index, lessonTitle);

                            String exOne = lessonTitle + "-Exercise";
                            String exTwo = lessonTitle2 + "-Exercise";
                            if (schedule.contains(exOne)) {
                                schedule.remove(schedule.indexOf(exOne));
                                schedule.add(schedule.indexOf(lessonTitle + 1), exOne);
                            }
                            if (schedule.contains(exTwo)) {
                                schedule.remove(schedule.indexOf(exTwo));
                                schedule.add(schedule.indexOf(lessonTitle2) + 1, exTwo);
                            }
                        }
                        break;
                    case "Exercise":
                        //упражнение -> Objects-Exercise
                        //[Data Types, Objects, Lists]
                        String exercise = lessonTitle + "-Exercise";
                        //слагаме упражнение ако има лекция и го няма
                        int indexLessonTitle = schedule.indexOf(lessonTitle);
                        // what is this "if" for??
                        if(schedule.contains(lessonTitle)) {
                            //има ли упражнение
                            if(indexLessonTitle == schedule.size() - 1) {
                                schedule.add(indexLessonTitle + 1, exercise);
                            } else  if(!schedule.get(indexLessonTitle + 1).equals(exercise)) {
                                schedule.add(indexLessonTitle + 1, exercise);
                            }
                        } else {
                            schedule.add(lessonTitle);
                            schedule.add(exercise);
                        }
                        break;
                }

                input = scanner.nextLine();
            }

            printList(schedule);
        }

        private static void printList(List<String> elements) {
            int count = 1;
            for (String element : elements) {
                System.out.println(count + "." + element);
                count++;

            }
        }
    }