using System;

using System.Linq;

using System.Collections.Generic;

class Program {

    public record MyClass(string Z, string T, int Y);

​

    public static string Case4() {

        var I = new MyClass("Forever", "foo", 11); int III = 3;

        var II = Enumerable.Repeat(I, III)

            .Select(i => i with { T = i.T + i.Y })

            .ToList().ToDictionary(_ => --III);

        var IIII = II.Select(p3 => p3.Value with { Y = p3.Key.ToString().Length });

        return IIII.Sum(p5 => p5.T.Length).ToString();

    }

    public static string Case3() {

        var I = new MyClass("Asd", "foo", 11); int III = 1;

        var II = Enumerable.Repeat(I, III)

            .Select(i => i with { Y = ++III % 2 })

            .ToList().ToDictionary(_ => III++);

        var charmander = II.GroupBy(a => a.Value);

        charmander.OrderByDescending(c => c.Key);

        return charmander.First().ToString();

    }

    public static string Case2() {

        IEnumerable<(string N, int U)> list =

            new List<(string, int)>() {

            new("foo", 1), new("bur", 2), new("baz3", 3), new("foo12", 1),

            new("ba",2 ), new("fu", 3), new("fubar",4 ), new("bazbur", 5) };

        var test = list.Where(

            x => x.N.Length == list.Max(l => l.N.Length))

            .SelectMany(t => t.N)

            .Where(x => x.ToString().Length < list.Max(l => l.N.Length) - 1);

        return test.Last().ToString();

    }

    public static string Case1() {

        IEnumerable<(string N, string U)> list =

            new List<(string, string)>() {

            new("foo", "1"), new("bur", "2"), new("baz3pikachu", "3"),

            new("foo12", "1"), new("ba", "2"), new("fu", "3"),

            new("fubar", "4"), new("bazbur", "5")};

        return list

            .GroupBy(x => x.N.Length == list.Max(l => l.N.Length) ? "x" : "y")

            .ToList().Last().Key;

​

    }

​

    static void Main(string[] args) {

        Console.WriteLine(Case1());

        Console.WriteLine(Case2());

        Console.WriteLine(Case3());

        Console.WriteLine(Case4());

    }

}