using System;

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​

​

​

​

public class Program

{ 

    /*

    Complete the function below which takes a dollar value and writes it out in

    words. It's not a trick question but has a few logic details to work out.

    We're interested in:

    * How you solve a problem

    * Clean, concise code, which communicates your ideas clearly

    * Good understanding of unit testing

​

    Some tests are given below, but they aren't complete. Consider other cases and

    how you might handle them.

​

    There isn't any time limit but it shouldn't take more than a couple of hours,

    and if you are really stuck please get in touch for a hint. We work in a team

    in the real world so sensible questions wont be considered a failure!

    */

    public class MoneyTypes

    {

        public int Thousands { get; set; }

        public int Hundreds { get; set; }

        public int Tens { get; set; }

        public int Cents { get; set; }

​

        public MoneyTypes(int thousands, int hundreds, int tens, int cents)

        {

            Thousands = thousands;

            Hundreds = hundreds;

            Tens = tens;

            Cents = cents;

        }

​

    }   

    public class WordConversionService

    {

​

        public string Execute(decimal number)

        {

            var data = MoneyConversion(number);

            return ConvertToWord(data);

​

        }

        private MoneyTypes MoneyConversion(decimal number)

        {

​

            var dollars = decimal.ToInt32(number);

            var cents = 0;

​

            var split = number.ToString()?.Split(".");

            if (split.Length > 1)

            {

                cents = int.Parse(split[1]);

            }

​

            var thousands = (dollars % 10000) / 1000;

            var hundreds = (dollars % 1000) / 100;

            var tens = (dollars % 100);

​

            return new MoneyTypes(thousands, hundreds, tens, cents);

        }

​

        private string ConvertToWord(MoneyTypes moneyTypes)

        {

            var finalString = ConvertThousands(moneyTypes.Thousands);

            if (moneyTypes.Hundreds > 0 )

            {

                var hundreds = ConvertHundreds(moneyTypes.Hundreds);

                finalString += hundreds;

            }

​

            if (moneyTypes.Tens > 0)

            {

                var tens = ConvertTens(moneyTypes.Tens);

                finalString += (finalString == string.Empty) ? tens : " and " + tens;

            }

​

            finalString += Dollars(moneyTypes);

​

            if (moneyTypes.Cents > 0 )

            {

                var cents = ConvertTens(moneyTypes.Cents);

                finalString += finalString == string.Empty ? cents : " and " + cents; ;

            }

​

            finalString += Cents(moneyTypes.Cents);

            return finalString;

        }

​

        private string ConvertSingleNumber(int number)

        {

            switch (number)

            {

​

                case 1:

                    return "one";

                case 2:

                    return "two";

                case 3:

                    return "three";

                case 4:

                    return "four";

                case 5:

                    return "five";

                case 6:

                    return "six";

                case 7:

                    return "seven";

                case 8:

                    return "eight";

                case 9:

                    return "nine";

                default:

                    return string.Empty;

            }

        }

​

        private string ConvertDoubleNumber(int tens, int ones)

        {

​

            var oneWords = ConvertSingleNumber(ones);

​

            if (tens == 0)

            {

                return ConvertSingleNumber(ones);

            }

​

            if (ones > 0)

            {

                oneWords = " " + oneWords;

​

            }

​

            switch (tens)

            {

                case 1:

                    return ConvertDoubleStartingWithOnes(ones);

                case 2:

                    return "twenty" + oneWords;

                case 3:

                    return "thirty" + oneWords;

                case 4:

                    return "fourty" + oneWords;

                case 5:

                    return "fifty" + oneWords;

                case 6:

                    return "sixty" + oneWords;

                case 7:

                    return "seventy" + oneWords;

                case 8:

                    return "eighty" + oneWords;

                case 9:

                    return "ninety" + oneWords;

            }

            return string.Empty;

​

        }

​

        private string ConvertDoubleStartingWithOnes(int ones)

        {

            switch (ones)

            {

                case 0:

                    return "ten";

                case 1:

                    return "eleven";

                case 2:

                    return "twelve";

                case 3:

                    return "thirteen";

                case 4:

                    return "fourteen";

                case 5:

                    return "fifteen";

                case 6:

                    return "sixteen";

                case 7:

                    return "seventeen";

                case 8:

                    return "eighteen";

                case 9:

                    return "nineteen";

                default:

                    return string.Empty;

            }

        }

​

        private string ConvertThousands(int number)

        {

            return number > 0 ? (ConvertSingleNumber(number) + " thousand") : string.Empty;

        }

​

        private string ConvertHundreds(int number)

        {

            return number > 0 ? (ConvertSingleNumber(number) + " hundred") : string.Empty;

        }

​

        private string ConvertTens(int number)

        {

            var tens = (number % 100) / 10;

            var ones = number % 10;

            return ConvertDoubleNumber(tens, ones);

        }

​

        private string Dollars(MoneyTypes moneyType)

        {

            var totalAmount = moneyType.Thousands + moneyType.Hundreds + moneyType.Tens;

            if (totalAmount == 1 && moneyType.Tens == 1)

            {

                return " dollar";

            }

            if (totalAmount > 0)

            {

                return " dollars";

            }

            return string.Empty;

​

        }

​

        private string Cents(int cents)

        {

            if (cents == 0)

            {

                return string.Empty;

            }

​

            if (cents == 1)

            {

                return " cent";

            }

​

            return " cents";

​

        }

    }

​

​

    /// <summary>

    /// Write out a dollar value in words. Handles values less than $1,000, and

    /// up to two decimal places.

    /// </summary>

    static string DollarsToWords(decimal value)

    {

        if (value == decimal.Zero)

        {

            return "zero dollars";

        }

        if (value > 1000)

        {

            return "Error: Value too high, enter a value below 1000.";

        }

​

        var wordConversionService = new WordConversionService();

        var words = wordConversionService.Execute(value);

        return words;

    }

    public static void Main()

    {

        Test(0.12m, "twelve cents");

        Test(10.55m, "ten dollars and fifty five cents");

        //The test was wrong, it should be dollar instead of cents

        Test(120, "one hundred and twenty dollars");

        Test(99, "ninety nine dollars");

        Test(91, "ninety one dollars");

        Test(0.99m, "ninety nine cents");

        // use non plurals

        Test(0.01m, "one cent");

        Test(1, "one dollar");

​

        Test(1000, "one thousand dollars");

        Test(901, "nine hundred and one dollars");

        Test(0, "zero dollars");

        Test(10000, "Error: Value too high, enter a value below 1000.");

    }

​

    static void Test(decimal number, string expected)

    {

        var actual = DollarsToWords(number);

        if (actual == expected)

        {

            Console.WriteLine($"{number}: PASS");

            return;

        }

        Console.WriteLine($"{number}: FAIL");

        Console.WriteLine($"  Expected: {expected}");

        Console.WriteLine($"  Actual:   {actual}");

        Console.WriteLine();

    }

}