using System.Diagnostics;

public enum TimeFrame {
    Year, TwoYears, Long
}

public class Paper {
    public string Name { get; set; }
    public Person Author { get; set; }
    public DateTime PublicationDate { get; set; }

    public Paper(string name, Person author, DateTime publicationDate) {
        Name = name;
        Author = author;
        PublicationDate = publicationDate;
    }

    public Paper() {
        Name = "Paper Name";
        Author = new Person("", "");
        PublicationDate = DateTime.Now;
    }

    public override string ToString() {
        return $"Paper \"{Name}\" by {Author}, published at {PublicationDate:yyyy-MM-dd HH:mm}";
    }
}

public class ResearchTeam {
    private string _topic;
    private string _organization;
    private int _registrationNumber;
    private TimeFrame _researchTimeFrame;
    private Paper[] _papers;

    public Paper? LastPaper {
        get {
            return _papers.MaxBy(p => p.PublicationDate);
        }
    }
    public bool this[TimeFrame timeFrame] {
        get {
            return _researchTimeFrame == timeFrame;
        }
    }

    public string Topic {
        get {
            return _topic;
        }
    }
    public string Organization {
        get {
            return _organization;
        }
    }
    public int RegistrationNumber {
        get {
            return _registrationNumber;
        }
    }
    public TimeFrame ResearchTimeFrame {
        get {
            return _researchTimeFrame;
        }
    }
    public Paper[] Papers {
        get {
            return _papers;
        }
    }

    public ResearchTeam(string topic, string organization, int registrationNumber, TimeFrame researchTimeFrame) {
        _topic = topic;
        _organization = organization;
        _registrationNumber = registrationNumber;
        _researchTimeFrame = researchTimeFrame;
        _papers = Array.Empty<Paper>();
    }

    public ResearchTeam() {
        _topic = "Topic";
        _organization = "Organization";
        _registrationNumber = 0;
        _researchTimeFrame = TimeFrame.Year;
        _papers = Array.Empty<Paper>();
    }

    public void AddPapers(params Paper[] papers) {
        _papers = _papers.Concat(papers).ToArray();
    }

    public override string ToString() {
            return $"Research team \"{_topic}\" ({_organization}, {_registrationNumber}), " +
                   $"{_researchTimeFrame} time frame, {_papers.Length} papers: " +
                   $"{string.Join(", ", _papers.AsEnumerable())}";
    }
    public string ToShortString() {
        return $"Research team \"{_topic}\" ({_organization}, {_registrationNumber}), " +
               $"{_researchTimeFrame} time frame, {_papers.Length} papers";
    }
}

public class Person {
    public string FirstName { get; }
    public string LastName { get; }

    public Person(string firstName, string lastName) {
        FirstName = firstName;
        LastName = lastName;
    }

    public override string ToString() { return $"{FirstName} {LastName}"; }
}

class Program {
    public static void Main(string[] args) {
        var researchTeam = new ResearchTeam();
        Console.WriteLine("ResearchTeam.ToShortString(): {0}", researchTeam.ToShortString());

        foreach (var enumValue in Enum.GetValues<TimeFrame>()) {
            Console.WriteLine("ResearchTeam[{0}]: {1}", enumValue, researchTeam[enumValue]);
        }

        Console.WriteLine("===============================================================");

        researchTeam = new ResearchTeam("влияние мэшапов на стул по утрам",
            "ООО \"Разработка очка\"", 123, TimeFrame.Year);

        Console.WriteLine("ResearchTeam.ToShortString(): {0}", researchTeam);

        researchTeam.AddPapers(new Paper {
            Name = "напас лавандос вместо лоперамида",
            Author = new Person("хуй", "моржовый"),
            PublicationDate = new DateTime(2022, 5, 9, 12, 0, 0)
        }, new Paper {
            Name = "производство мэшапов из лоперамида",
            Author = new Person("кто", "такой"),
            PublicationDate = new DateTime(2021, 12, 1, 5, 0, 0)
        }, new Paper {
            Name = "мэшапы с меладзе как слабительное",
            Author = new Person("пиздец", "блядский"),
            PublicationDate = new DateTime(2021, 7, 15, 18, 0, 0)
        }, new Paper {
            Name = "мэшапы с новогодним поздравлением от путина: с новым мэшапом, пидоры!",
            Author = new Person("путин", "владимир"),
            PublicationDate = new DateTime(2021, 12, 31, 12, 0, 0)
        });

        Console.WriteLine("ResearchTeam.LastPaper: {0}", researchTeam.LastPaper);

        Console.WriteLine("===============================================================");

        var array1 = new Paper[10000];
        var array2 = new Paper[100][];
        var array3 = new Paper[100][];

        // init array1
        for (var i = 0; i < array1.Length; i++) {
            array1[i] = new Paper {
                Name = "paper" + i,
                Author = new Person("author" + i, "author" + i),
                PublicationDate = new DateTime(2021, 1, 1, 0, 0, 0)
            };
        }

        // init array2
        for (var i = 0; i < array2.Length; i++) {
            var arr = new Paper[100];
            for (var j = 0; j < arr.Length; j++) {
                arr[j] = new Paper {
                    Name = "paper" + i + j,
                    Author = new Person("author" + i + j, "author" + i + j),
                    PublicationDate = new DateTime(2021, 1, 1, 0, 0, 0)
                };
            }
            array2[i] = arr;
        }

        // init array3
        var random = new Random();
        for (var i = 0; i < array3.Length; i++) {
            var arr = new Paper[random.Next(50, 150)];
            for (var j = 0; j < arr.Length; j++) {
                arr[j] = new Paper {
                    Name = "paper" + i + j,
                    Author = new Person("author" + i + j, "author" + i + j),
                    PublicationDate = new DateTime(2021, 1, 1, 0, 0, 0)
                };
            }
            array3[i] = arr;
        }

        // test access to array1
        var sw = new Stopwatch();
        sw.Start();

        for (var i = 0; i < 10000000; i++) {
            var paper = array1[random.Next(0, array1.Length)];
            DoSomething(paper);
        }

        sw.Stop();
        Console.WriteLine("array1|access: {0}ms", sw.ElapsedMilliseconds);

        // test access to array2
        sw.Restart();

        for (var i = 0; i < 10000000; i++) {
            var paper = array2[random.Next(0, array2.Length)][random.Next(0, array2.Length)];
            DoSomething(paper);
        }

        sw.Stop();
        Console.WriteLine("array2|access: {0}ms", sw.ElapsedMilliseconds);

        // test access to array3
        sw.Restart();

        for (var i = 0; i < 10000000; i++) {
            var arr = array3[random.Next(0, array3.Length)];
            var paper = arr[random.Next(0, arr.Length)];
            DoSomething(paper);
        }

        sw.Stop();
        Console.WriteLine("array3|access: {0}ms", sw.ElapsedMilliseconds);

        // test write to array1
        sw.Restart();

        for (var i = 0; i < 10000000; i++) {
            array1[random.Next(0, array1.Length)] = new Paper {
                Name = "paper" + i,
                Author = new Person("author" + i, "author" + i),
                PublicationDate = new DateTime(2021, 1, 1, 0, 0, 0)
            };
        }

        sw.Stop();
        Console.WriteLine("array1|write: {0}ms", sw.ElapsedMilliseconds);

        // test write to array2
        sw.Restart();

        for (var i = 0; i < 10000000; i++) {
            array2[random.Next(0, array2.Length)][random.Next(0, array2.Length)] = new Paper {
                Name = "paper" + i,
                Author = new Person("author" + i, "author" + i),
                PublicationDate = new DateTime(2021, 1, 1, 0, 0, 0)
            };
        }

        sw.Stop();
        Console.WriteLine("array2|write: {0}ms", sw.ElapsedMilliseconds);

        // test write to array3
        sw.Restart();

        for (var i = 0; i < 10000000; i++) {
            var arr = array3[random.Next(0, array3.Length)];
            arr[random.Next(0, arr.Length)] = new Paper {
                Name = "paper" + i,
                Author = new Person("author" + i, "author" + i),
                PublicationDate = new DateTime(2021, 1, 1, 0, 0, 0)
            };
        }

        sw.Stop();
        Console.WriteLine("array3|write: {0}ms", sw.ElapsedMilliseconds);
    }

    private static void DoSomething(Paper paper) {

    }
}