using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        double[] arr1 = new double[] {1, 2};

        double[] arr2 = new double[] {3, 4};

        var concatArr = arr1.Concat(arr2);

        Console.WriteLine("Try #1");

        foreach (var i in concatArr)

        {

            Console.WriteLine(i);

        }

        Console.WriteLine("Try #2");

        foreach (var i in concatArr)

        {

            Console.WriteLine(i);

            arr2[0] = 10;

        }

    }

}