[НП] - File System

import java.time.LocalDateTime;
import java.util.*;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

class File implements Comparable<File>{
    private String name;
    private Integer size;
    private LocalDateTime createdAt;

    public File(String name, Integer size, LocalDateTime createdAt) {
        this.name = name;
        this.size = size;
        this.createdAt = createdAt;
    }

    public String getName() {
        return name;
    }

    public Integer getSize() {
        return size;
    }

    public LocalDateTime getCreatedAt() {
        return createdAt;
    }

    public int getYear(){
        return createdAt.getYear();
    }

    @Override
    public String toString() {
        return String.format("%-10s %5dB %s", name,size,createdAt.toString());
    }

    @Override
    public int compareTo(File o) {
        if (createdAt.equals(o.createdAt)){
            if (name.equals(o.name))
                return Integer.compare(size, o.size);
            return name.compareTo(o.name);
        }
        return createdAt.compareTo(o.createdAt);
    }
}

class FileSystem{
    Map<Character, Set<File>> map;

    public FileSystem() {
        this.map = new HashMap<>();
    }

    public void addFile(char folder, String name, int size, LocalDateTime createdAt){
        map.computeIfAbsent(folder, (k) -> map.put(folder, new TreeSet<>(File::compareTo)));
        map.get(folder).add(new File(name, size, createdAt));
    }

    public List<File> findAllHiddenFilesWithSizeLessThen(int size){
        return map.values().stream()
                .flatMap(Collection::stream)
                .filter(file -> file.getSize()<size && file.getName().startsWith("."))
                .collect(Collectors.toList());
    }

    public int totalSizeOfFilesFromFolders(List<Character> folders){
        int sum = folders.stream().mapToInt(folder -> map.get(folder).stream().mapToInt(File::getSize).sum()).sum();
        return sum;
    }

    public Map<Integer, Set<File>> byYear(){
        return map.values().stream()
                .flatMap(Collection::stream)
                .collect(Collectors.groupingBy(File::getYear, Collectors.toSet()));
    }

    public Map<String, Long> sizeByMonthAndDay(){
        Map<String,Long> result = new HashMap<>();
        map.values().stream()
                .flatMap(Collection::stream) //strim na datoteki
                .forEach(file -> {
                    String key = file.getCreatedAt().getMonth().toString()+"-"+file.getCreatedAt().getDayOfMonth();
                    result.computeIfAbsent(key, (k) -> result.put(key, (long) 0));
                    result.put(key, result.get(key)+file.getSize());
                });
        return result;
    }
}

public class FileSystemTest {
    public static void main(String[] args) {
        FileSystem fileSystem = new FileSystem();
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        scanner.nextLine();
        for (int i = 0; i < n; i++) {
            String line = scanner.nextLine();
            String[] parts = line.split(":");
            fileSystem.addFile(parts[0].charAt(0), parts[1],
                    Integer.parseInt(parts[2]),
                    LocalDateTime.of(2016, 12, 29, 0, 0, 0).minusDays(Integer.parseInt(parts[3]))
            );
        }
        int action = scanner.nextInt();
        if (action == 0) {
            scanner.nextLine();
            int size = scanner.nextInt();
            System.out.println("== Find all hidden files with size less then " + size);
            List<File> files = fileSystem.findAllHiddenFilesWithSizeLessThen(size);
            files.forEach(System.out::println);
        } else if (action == 1) {
            scanner.nextLine();
            String[] parts = scanner.nextLine().split(":");
            System.out.println("== Total size of files from folders: " + Arrays.toString(parts));
            int totalSize = fileSystem.totalSizeOfFilesFromFolders(Arrays.stream(parts)
                    .map(s -> s.charAt(0))
                    .collect(Collectors.toList()));
            System.out.println(totalSize);
        } else if (action == 2) {
            System.out.println("== Files by year");
            Map<Integer, Set<File>> byYear = fileSystem.byYear();
            byYear.keySet().stream().sorted()
                    .forEach(key -> {
                        System.out.printf("Year: %d\n", key);
                        Set<File> files = byYear.get(key);
                        files.stream()
                                .sorted()
                                .forEach(System.out::println);
                    });
        } else if (action == 3) {
            System.out.println("== Size by month and day");
            Map<String, Long> byMonthAndDay = fileSystem.sizeByMonthAndDay();
            byMonthAndDay.keySet().stream().sorted()
                    .forEach(key -> System.out.printf("%s -> %d\n", key, byMonthAndDay.get(key)));
        }
        scanner.close();
    }
}