gistfile1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace MarkVShaney
{
  class MarkVShaney
  {
    private Dictionary<string, List<string>> table;
    private string firstWord;
    private string secondWord;
    private Random random;

    public MarkVShaney(string fileName)
    {
      random = new Random(Guid.NewGuid().GetHashCode());
      table = new Dictionary<string, List<string>>();

      string text = File.ReadAllText(fileName);
      string[] words = text.Split(' ');

      int overloaded = 0;

      int i = 0;
      firstWord = words[i++];
      secondWord = words[i++];

      string first = firstWord;
      string second = secondWord;

      while (i < words.Length)
      {
        string third = words[i++];

        string key = first + second;

        if (!table.ContainsKey(key))
          table.Add(key, new List<string>());
        else
          ++overloaded;

        table[key].Add(third);

        first = second;
        second = third;
      }

      System.Console.WriteLine("Words count: " + words.Length.ToString());
      System.Console.WriteLine("Keys count: " + table.Keys.Count.ToString());
      System.Console.WriteLine("Overloaded keys count: " + overloaded.ToString() + '\n');
    }

    public string GenerateSomeText(int wordsCount)
    {
      if (wordsCount < 3)
        return String.Empty;

      StringBuilder sb = new StringBuilder();

      sb.Append(firstWord + ' ');
      sb.Append(secondWord + ' ');
      wordsCount -= 2;

      string first = firstWord;
      string second = secondWord;

      while (wordsCount > 0)
      {
        string key = first + second;

        if (!table.ContainsKey(key))
          break;

        string third = table[key].ToArray()[random.Next(table[key].Count)];
        sb.Append(third + ' ');

        first = second;
        second = third;
        
        --wordsCount;
      }

      return sb.ToString();
    }
  }

  class Program
  {
    static void Main(string[] args)
    {
      MarkVShaney shaney = new MarkVShaney("text.txt");
      System.Console.WriteLine(shaney.GenerateSomeText(1000));
      System.Console.Read();
    }
  }
}