using System;

using System.Linq;

using NUnit.Framework;

using NUnitLite;

​

public class HexDigitCalculator

{

    public static string CompareOddEvenHexDigits(string hexNumber)

    {

        if (string.IsNullOrEmpty(hexNumber))

        {

            return "Invalid input: Null or empty hexadecimal number.";

        }

​

        hexNumber = hexNumber.ToUpper();

​

        if (hexNumber.StartsWith("0X"))

        {

            hexNumber = hexNumber.Substring(2);

        }

​

        if (!IsValidHexadecimal(hexNumber))

        {

            return "Invalid input: Not a valid hexadecimal number.";

        }

​

        int sumOfOddDigits = 0;

        int sumOfEvenDigits = 0;

​

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

        {

            int digitValue = GetDigitValue(hexNumber[i]);

​

            if (digitValue % 2 == 0)

            {

                sumOfEvenDigits += digitValue;

            }

            else

            {

                sumOfOddDigits += digitValue;

            }

        }

​

        if (sumOfOddDigits > sumOfEvenDigits)

        {

            return "greater odds";

        }

        else if (sumOfOddDigits < sumOfEvenDigits)

        {

            return "lesser odds";

        }

        else

        {

            return "same odds and evens";

        }

    }

​

    private static bool IsValidHexadecimal(string hexNumber)

    {

        return hexNumber.All(c => (c >= '0' && c <= '9') || (c >= 'A' && c <= 'F'));

    }

​

    private static int GetDigitValue(char hexChar)

    {

        if (hexChar >= '0' && hexChar <= '9')

        {

            return hexChar - '0';

        }

        else if (hexChar >= 'A' && hexChar <= 'F')

        {

            return hexChar - 'A' + 10;

        }

        else

        {

            throw new ArgumentException("Invalid hexadecimal character."); // Should not happen due to validation

        }

    }

    public static int Main(string[] args)

    {

        return new AutoRun().Execute(args);

    }

}

​

​

public class HexDigitCalculatorTests

{

    [Test]

    public void CompareOddEvenHexDigits_GreaterOdds()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("3A2F5B"), Is.EqualTo("greater odds"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_LesserOdds()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("13A24"), Is.EqualTo("lesser odds"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_SameOddsAndEvens()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("3A4B"), Is.EqualTo("same odds and evens"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_EdgeCaseAllOdds()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("13579F"), Is.EqualTo("greater odds"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_EdgeCaseAllEvens()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("02468A"), Is.EqualTo("lesser odds"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_EdgeCaseMixedLargeHex()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("ABCDEF0123456789"), Is.EqualTo("same odds and evens"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_InvalidInputNonHexCharacters()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("123G"), Is.EqualTo("Invalid input: Not a valid hexadecimal number."));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_NullInput()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits(null), Is.EqualTo("Invalid input: Null or empty hexadecimal number."));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_EmptyInput()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits(""), Is.EqualTo("Invalid input: Null or empty hexadecimal number."));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_HexWithPrefixLower()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("0x3A2F5B"), Is.EqualTo("greater odds"));

    }

​

     [Test]

    public void CompareOddEvenHexDigits_HexWithPrefixUpper()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("0X3A2F5B"), Is.EqualTo("greater odds"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_SingleDigitOdd()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("1"), Is.EqualTo("greater odds"));

    }

​

    [Test]

    public void CompareOddEvenHexDigits_SingleDigitEven()

    {

        Assert.That(HexDigitCalculator.CompareOddEvenHexDigits("2"), Is.EqualTo("lesser odds"));

    }

}