C#

bool loginResult = false;

using (DirectoryEntry de = new DirectoryEntry(this.SearchRoot.Path, userDN, password, AuthenticationTypes.Secure))
                {
                    try
                    {
                        object x = de.NativeObject;
                        loginResult = true;
                    }
                    catch (COMException comEx)
                    {
                    }
return loginResult
      
}

List<string> dictionary = new List<string>()

// get the next sentence to process (you have to write 
// the GetNextSentence function)
string sentence = GetNextSentence();
// split the sentence into words
string[] words = sentence.ToLower().Split(' ');
// for each word
for (int i = 0; i < words.Length; i++)
{
    // if it's not already in the dictionary using the 
    // List.Contains method
    if (!dictionary.Contains(words[i])
    {
        // add it to the dictionary
        dictionary.Add(words[i]);
    }
}