Коригираният код на 04. List Operations

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

public class ListOperations_04 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        List<Integer> numbers = Arrays.stream(scanner.nextLine().split("\\s+"))
                .map(Integer::parseInt)
                .collect(Collectors.toList());

        String command = scanner.nextLine();
        while (!command.equals("End")) {
            String[] commandParts = command.split(" ");
            String commandName = commandParts[0];
            switch (commandName) {
                case "Add":
                    int numberToAdd = Integer.parseInt(commandParts[1]);
                    numbers.add(numberToAdd);
                    break;
                case "Insert":
                    int numberToInsert = Integer.parseInt(commandParts[1]);
                    int indexToInsert = Integer.parseInt(commandParts[2]);
                    if (isValidIndex(indexToInsert, numbers.size())) {
                        numbers.add(indexToInsert, numberToInsert);
                    } else {
                        System.out.println("Invalid index");
                    }
                    break;
                case "Remove":
                    int indexToRemove = Integer.parseInt(commandParts[1]);
                    if (isValidIndex(indexToRemove, numbers.size())) {
                        numbers.remove(indexToRemove);
                    } else {
                        System.out.println("Invalid index");
                    }
                    break;
                case "Shift":
                    int count = Integer.parseInt(commandParts[2]);
                    if (commandParts[1].equals("left")) {
                        shiftLeft(numbers, count);
                    } else if (commandParts[1].equals("right")) { //corrected code
                        shiftRight(numbers, count);
                    }
                    break;
            }
            command = scanner.nextLine();
        }

        for (int number : numbers) {
            System.out.print(number + " ");
        }
    }

    private static boolean isValidIndex(int index, int size) {
        return index >= 0 && index < size;
    }

    private static void shiftLeft(List<Integer> numbers, int count) {
        for (int i = 0; i < count; i++) {
            int firstElement = numbers.remove(0);
            numbers.add(firstElement);
        }
    }

    private static void shiftRight(List<Integer> numbers, int count) {
        for (int i = 0; i < count; i++) {
            int lastElement = numbers.remove(numbers.size() - 1);
            numbers.add(0, lastElement);
        }
    }
}