Question

Last night I was messing around with Piglatin using Arrays and found out I could not reverse the process. How would I shift the phrase and take out the Char’s “a” and “y” at the end of the word and return the original word in the phrase.

For instance if I entered “piggy” it would come out as “iggypay” shifting the word piggy so “p” is at the end of the word and “ay” is appended.

Here is the example code so you can try it as well.

    public string ay;
    public string PigLatin(string phrase)
    {
        string[] pLatin;
        ArrayList pLatinPhrase = new ArrayList();
        int wordLength;
        pLatin = phrase.Split();

        foreach (string pl in pLatin)
        {
            wordLength = pl.Length;
            pLatinPhrase.Add(pl.Substring(1, wordLength - 1) + pl.Substring(0, 1) + "ay");
        }

        foreach (string p in pLatinPhrase)
        {
            ay += p; 
        }
        return ay;
    }

You will notice that is example is not programmed to find vowels and append them to the end along with “ay”. Just simply a basic way of doing it.

If you where wondering how to reverse the above try this example of uPiglatinify

    public string way;
    public string uPigLatinify(string word)
    {
        string[] latin;
        int wordLength;
        // Using arrraylist to store split words.
        ArrayList Phrase = new ArrayList();
        // Split string phrase into words.
        latin = word.Split(' ');

        foreach (string i in latin)
        {
            wordLength = i.Length;
            if (wordLength > 0)
            {
                // Grab 3rd letter from the end of word and append to front
                // of word chopping off "ay" as it was not included in the indexing.
                Phrase.Add(i.Substring(wordLength - 3, 1) + i.Substring(0, wordLength - 3) + " ");
            }
        }

        foreach (string _word in Phrase)
        {
            // Add words to string and return.
            way += _word;
        }
        return way;
    }

Answer 1

The work to split the phrase into words and recombine the words after transforming them is the same as in the original case. The difficulty is in un-pig-latin-ifying an individual word. With some error checking, I imagine you could do this:

string UnPigLatinify(string word)
{
    if ((word == null) || !Regex.IsMatch(word, @"^\w+ay$", RegexOptions.IgnoreCase))
        return word;

    return word[word.Length - 3] + word.Substring(0, word.Length - 3);
}

The regular expression just checks to make sure the word is at least 3 letters long, composed of characters, and ends with “ay”.

The actual transform takes the third to last letter (the original first letter) and appends the rest of the word minus the “ay” and the original letter.

Is this what you meant?