Welcome to the Lounge

string LookAndSay(int S, int n)
{
    string result = S.ToString();
    for (int i = 0; i < (n - 1); i++)
    {
        StringBuilder NewString = new StringBuilder();
        for (int j = 0; j < result.Length; j++)
        {
            string part = RepetingItems(j, result);
            j += (int)char.GetNumericValue(part[0]) - 1;
            NewString.Append(part);
        }
        result = NewString.ToString();
    }
    return result;
}


string RepetingItems(int index, string array)
{
    int count = 1;
    for (int i = index + 1; i < array.Length; i++)
    {
        if (array[index] == array[i])
        { count++; }
        else { break; }

    }
    return (count.ToString() + array[index].ToString());
}

        static void Main(string[] args)
        {
            string result = ("1");

<pre>
        int i = 1;

        do
        {
            Console.WriteLine(i.ToString() + "\t" + result.Length.ToString());

            result = GetNextResult(result);
            i += 1;
        }
        while (i < 101);

        Console.ReadLine();

    }

    static string GetNextResult(string origin)
    {
        char character;
        int occurences;
        StringBuilder result = new StringBuilder();

        do
        {
            if (origin.Length == 0)
                break;

            ProcessNextGroup(origin, out character, out occurences);

            origin = origin.Substring(occurences);

            result.Append(occurences.ToString());
            result.Append(character.ToString());

            GC.Collect();

        }
        while (true);

        return result.ToString();

    }

    static void ProcessNextGroup(string sequence, out char character, out int occurences)
    {
        int index = 0;
        character = sequence[0];
        occurences = 1;

        do
        {
            if (++index > (sequence.Length -1))
                break;

            if (sequence[index] == character)
                occurences += 1;
            else
                break;
        }
        while (true);
    }
}</pre>

PeejayAdams wrote:

written on a whim in "do ... while" loops because someone recently said "for" loops are for dinosaurs

string LookAndSayFile(int S, int n)
       {
           //If the string is above this length split it into multiple strings
           int SplitStringSize = 2;

           //Setting the directory where files are stored relativce to the exe file
           string projectPath = System.IO.Path.GetFullPath(@"..\..\..\..\");

           //Delete files
           File.Delete(projectPath + "output.txt");
           File.Delete(projectPath + "input.txt");

           //Add intput and and empty file
           System.IO.File.WriteAllLines(projectPath + "output.txt", new string[] { string.Empty });
           System.IO.File.WriteAllLines(projectPath + "input.txt", new string[] { S.ToString() });


           //Number of iterations you want to perform
           for (int i = 0; i < (n - 1); i++)
           {

               char currentItem = '#';
               int count = 1;
               StringBuilder NewString = new StringBuilder();

               using (StreamReader sr = new StreamReader(projectPath + "input.txt"))
               {
                   while (sr.Peek() >= 0)
                   {

                       string res = sr.ReadLine();

                       foreach (char j in res)
                       {
                           if (currentItem == '#')
                           {
                               currentItem = j;
                               continue;
                           }

                           if (currentItem == j)
                           {
                               count++;
                           }
                           else
                           {
                               NewString.Append(count.ToString() + currentItem.ToString());
                               if (NewString.Length > SplitStringSize)
                               {
                                   System.IO.File.AppendAllLines(projectPath + "output.txt", new string[] { NewString.ToString() });
                                   NewString.Length = 0;
                               }
                               currentItem = j;
                               count = 1;
                               continue;
                           }

                       }
                   }
               }

               NewString.Append(count.ToString() + currentItem.ToString());
               System.IO.File.AppendAllLines(projectPath + "output.txt", new string[] { NewString.ToString() });
               File.Delete(projectPath + "input.txt");
               System.IO.File.Copy(projectPath + "output.txt", projectPath + "input.txt");
               System.IO.File.WriteAllText(projectPath + "output.txt", string.Empty);
           }
           return String.Join(Environment.NewLine, System.IO.File.ReadAllLines(projectPath + "input.txt"));
       }