using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var one = (new [] {

            new[] {"a", "b"},

            new[] {"c", "d"}

        })

            .SelectMany(a => a)

            .ToArray();

        var two = (new [] {

            new[] {"a", "b", "c"},

            new[] {"d"}

        })

            .SelectMany(a => a)

            .ToArray();

        Console.WriteLine(one.Length);

        Console.WriteLine(two.Length);

        Console.WriteLine("--");

        Console.WriteLine(one[0]);

        Console.WriteLine(two[0]);

        Console.WriteLine("--");

        Console.WriteLine(one[1]);

        Console.WriteLine(two[1]);

        Console.WriteLine("--");

        Console.WriteLine(one[2]);

        Console.WriteLine(two[2]);

        Console.WriteLine("--");

        Console.WriteLine(one[3]);

        Console.WriteLine(two[3]);

    }

}