using System;

using System.Collections.Generic;

public class Program

{

    private static Func<int, string> GenMax => (size) => new string('9', size);

    private static readonly string max9 = GenMax(9);

    private static readonly string max5 = GenMax(5);

    public static void Main()

    {

        Console.WriteLine(max9);

        Console.WriteLine(max5);

    }

}

​