using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

            FindAllNumbers obj = new FindAllNumbers();

            obj.Run();

    }

}

​

​

public class FindAllNumbers

{

    public int[] first = new int[] { 2, 4, 6, 9, 10, 11, 12, 13, 14, 15,16,19 };

    public int[] second = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,12, 12, 17,17,17,17,17,18,19 };

​

    public void Run()

    {

        Find();

        Console.ReadLine();

    }

​

    public void Find() {

            int j = 0;

            for (int i = 0; i < first.Length; i++) {

                if (j < second.Length-1)

                {

                    if (second[j+1] > first[i])

                        Console.WriteLine("First arr item = {0}, second array item = {1}", first[i], second[j - 1]);

                    else {

                        do

                        {

                            j = j + 1;

                            if (j == second.Length)

                            {

                                break;

                            }

                        }

                        while ((j == second.Length) || (second[j] < first[i]));

                        Console.WriteLine("First arr item = {0}, second array item = {1}", first[i], second[j - 1]);

                    }

                }

                else {

                    if (first[i] > second[second.Length-1])

                    {

                        Console.WriteLine("First arr item = {0}, second array item = {1}", first[i], second[j]);

                    }

                }

            }

    }

}