SantasGifts

package MidExamPreparation.MidExamRetake10Jan19;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

public class O2SantasGifts {
    public static void main(String[] args) throws IOException {
        BufferedReader reader =
            new BufferedReader(
                new InputStreamReader(
                    System.in
                )
            );

        int numberOfCommands = Integer.parseInt(reader.readLine());

        List<Integer> houses = Arrays.stream(reader.readLine().split("\\s+"))
                .map(Integer::parseInt)
                .collect(Collectors.toList());

        String line;
        int lastPosition = 0;
        int currentPosition =0;
        for (int i = 0; i < numberOfCommands; i++) {
            line = reader.readLine();

            String[] token = line.split("\\s+");
            String command = token[0].toLowerCase();

            switch (command) {
                case "forward" :
                    currentPosition += Integer.parseInt(token[1]);
                    if (currentPosition >= 0 && currentPosition <= houses.size()-1) {
                            houses.remove(currentPosition);
                    } else {
                        currentPosition -= Integer.parseInt(token[1]);
                    }
                    break;

                case "back" :
                    currentPosition -= Integer.parseInt(token[1]);
                    if (currentPosition >= 0 && currentPosition <= houses.size()-1) {
                        houses.remove(currentPosition);
                    } else {
                        currentPosition += Integer.parseInt(token[1]);
                    }
                    break;

                case "gift" :
                    if (Integer.parseInt(token[1]) >= 0 &&
                            Integer.parseInt(token[1]) < houses.size()
                    ) {
                        houses.add(Integer.parseInt(token[1]), Integer.parseInt(token[2]));
                        currentPosition = Integer.parseInt(token[1]);
                    }
                    break;

                case "swap" :
                    int first = houses.indexOf(Integer.parseInt(token[1]));
                    int second = houses.indexOf(Integer.parseInt(token[2]));

                    if ((first >= 0 &&
                            first < houses.size()) &&
                            (second >= 0 &&
                                    second < houses.size())
                    ) {
                        Collections.swap(houses, first, second);
                    }
                    break;
                    default:
                        break;
            }
            lastPosition = currentPosition;
        }

        System.out.printf("Position: %d%n", lastPosition);
        System.out.println(
                houses
                        .toString()
                        .replaceAll("[\\[\\]]", "")
        );
    }
}