using System;

using System.Collections.Generic;

using System.Linq;

using CsharpExtras.Extensions;

public class Program

{

    public static void Main()

    {

        string[,] sourceArray = new string[,]{{"Guidewire", "Is", "Great"}, {"Adapt", "And", "Succeed"}};

        string[,] arr1 = new string[,]{{"a111", "a112", "a113", "a114"}, {"a121", "a122", "a123", "a124"}};

        string[,] arr2 = new string[,]{{"a21"}, {"a22"}};

        string[,] arr3 = new string[3,0];

        string defaultValue = "xCenter";        

        var result = sourceArray.JoinRows(new List<string[,]>{arr1, arr2, arr3}, defaultValue);

        //DON'T CHANGE THIS

        string[,] expected = new string[,]{

            {"Guidewire", "Is", "Great", "xCenter"},

            {"Adapt", "And", "Succeed", "xCenter"},

            {"a111", "a112", "a113", "a114"},

            {"a121", "a122", "a123", "a124"}, 

            {"a21", "xCenter", "xCenter", "xCenter"},

            {"a22", "xCenter", "xCenter", "xCenter"},

            {"xCenter", "xCenter", "xCenter", "xCenter"},

            {"xCenter", "xCenter", "xCenter", "xCenter"},

            {"xCenter", "xCenter", "xCenter", "xCenter"}

        };

        var comparison = result.Compare(expected, string.Equals);

        Console.WriteLine(comparison.Message);

        Console.WriteLine("\nActual: ");

        PrintArray(result);

        Console.WriteLine("\nExpected: ");

        PrintArray(expected);

    }

​

    private static void PrintArray(string[,] arr)

    {

        for (int i = 0; i < arr.GetLength(0); i++)

            {

                Console.Write("| ");

                for (int k = 0; k < arr.GetLength(1); k++ )

                {

                    //put a single value

                    Console.Write(arr[i,k] + new string(' ', 10 - arr[i,k].Length));

                }

                Console.Write(" |");

                //next row

                Console.WriteLine();

            }

    }

}

​

public static class ArrayExtension2

{

    /*

        This function should stack the array arr on top of the others to give a new array.

        If the number of columns differs between the various arrays, the largest such number should be used, 

        and the defaultValue should be used to populate cells for rows which do not extend the full length of the resultant array.

        */

    public static TVal[,] JoinRows<TVal>(this TVal[,] arr, IEnumerable<TVal[,]> others, TVal defaultValue)

    {

        //Q1: Implement this

        //Q2: Sketch out test cases for this function

        var array = others.Prepend(arr);

        var columns = array.Select(item => item.GetLength(1)).Max();

        var rows = array.Select(item => item.GetLength(0)).Sum();

        var arrayCount = array.Count();

​

        TVal[,] result = new TVal[rows, columns];

        for(int e = 0, tempIndex = 0; e < arrayCount; e++) {

            var tempElem = array.ElementAt(e);

            int tempLenght = tempElem.GetLength(1);

            for(int i = 0; i < tempElem.GetLength(0); i++, tempIndex++) {

                for(int j = 0; j < columns; j++) {

                    result[tempIndex, j] = j >= tempLenght ? defaultValue : (TVal) tempElem.GetValue(i,j);

                }

            }

        }

        return result;

    }

}

​

​