The list of challenges were originally coded in C++. Challenge solution with

dates have been coded in C# and exist in this solution.

Challenge: C# Date: Class:

Kaprekars Constant 02/16/2021 Kaprekar

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace Coderbyte_CSharp.Hard_Challenges

class Kaprekar

{

// Have the function KaprekarsConstant(num) take the num parameter being passed

// which will be a 4-digit number with at least two distinct digits. Your program

// should perform the following routine on the number: Arrange the digits in

// descending order and in ascending order (adding zeroes to fit it to a 4-digit

// number), and subtract the smaller number from the bigger number. Then repeat

// the previous step. Performing this routine will always cause you to reach a

// fixed number: 6174. Then performing the routine on 6174 will always give you

// 6174 (7641 - 1467 = 6174). Your program should return the number of times

// this routine must be performed until 6174 is reached.

// For example: if num is 3524 your program should return 3 because of the

// following steps: (1) 5432 - 2345 = 3087, (2) 8730 - 0378 = 8352,

// (3) 8532 - 2358 = 6174.

public int KaprekarsConstant(int num)

{

int count = 0;

int remainder = num;

while (remainder != 6174)

{

remainder = descendInt(remainder) - ascendInt(remainder);

count++;

}

return count;

}

protected int ascendInt(int num)

{

int result = 0;

result = adjustInt(num, false);

return result;

}

protected int descendInt(int num)

{

int result = 0;

result = adjustInt(num, true);

return result;

}

private int adjustInt(int num, bool descend)

{

int result = 0;

int[] arr = new int[4];

int temp = num;

arr[0] = temp / 1000; temp -= arr[0] * 1000;

arr[1] = temp / 100; temp -= arr[1] * 100;

arr[2] = temp / 10; temp -= arr[2] * 10;

arr[3] = temp;

List<int> valueList = arr.ToList<int>();

if (descend)

{

valueList.Sort(SortDescend);

}

else

{

valueList.Sort();

}

result = valueList[0] * 1000 + valueList[1] * 100 + valueList[2] * 10 + valueList[3];

return result;

}

private int SortDescend(int a, int b)

{

int result = 0;

if (a > b)

{

result = -1;

}

else if (a < b)

{

result = 1;

}

else

{

result = 0;

}

return result;

}

}

<Compile Include="1 Easy Challenges\AlphabetSorter.cs" />

<Compile Include="1 Easy Challenges\MathSequence.cs" />

<Compile Include="1 Easy Challenges\NumberCheck.cs" />

<Compile Include="1 Easy Challenges\PalindromeChecker.cs" />

<Compile Include="1 Easy Challenges\StringIntersection.cs" />

<Compile Include="1 Easy Challenges\TimeConverter.cs" />

<Compile Include="2 Medium Challenges\ConsecutiveNumbers.cs" />

<Compile Include="2 Medium Challenges\NumberEncoder.cs" />

<Compile Include="2 Medium Challenges\PrimeNumber.cs" />

<Compile Include="2 Medium Challenges\StringCompression.cs" />

<Compile Include="2 Medium Challenges\StringMinimumWindow.cs" />

<Compile Include="2 Medium Challenges\StringReducer.cs" />

<Compile Include="2 Medium Challenges\StringUniqueSubstring.cs" />

<Compile Include="2 Medium Challenges\TreeGraphs.cs" />

<Compile Include="3 Hard Challenges\Kaprekar.cs" />

<Content Include="1 Easy Challenges\EasyChallenges.txt" />

<Content Include="2 Medium Challenges\MediumChallenges.txt" />

<Content Include="3 Hard Challenges\HardChallenges.txt" />

//tc.Test_TimeConvert();

//tc.Test_AlphabetSoup();

//tc.Test_ArithGeoSequence();

//tc.Test_Palindrome();

//tc.Test_NumberCheck();

//tc.Test_FindIntersection();

//tc.Test_Consecutive();

//tc.Test_KUniqueCharacters();

//tc.Test_NumberEncoding();

//tc.Test_PrimeMover();

//tc.Test_MinWindowSubstring();

//tc.Test_RunLength();

//tc.Test_StringReduction();

//tc.Test_TreeConstructor();

// Hard

tc.Test_KaprekarsConstant();

using Coderbyte_CSharp.Hard_Challenges;

public void Test_Consecutive()

#region Hard Challenges

public void Test_KaprekarsConstant()

{

Kaprekar k = new Kaprekar();

int value = 3524;

Console.WriteLine("Kaprekars Constant:");

Console.WriteLine("Input: {0} ", value);

Console.WriteLine("Output: {0}", k.KaprekarsConstant(value));

Console.WriteLine();

}

#endregion