Trie with association between words - algorithm

Question

I have a usecase where i want to correct words.
I have set of correct and incorrect words[spelling mistake].
I populate the trie with all words.
i have both the correct and incorrect version of every word.
Now in case if i get word as "a" for correction ,
-- i search it in trie.if trie has this word , i want to associate this word with the correct version of this word.
Solution :
i can set correct version ["a1"] of word at last node of incorrect word in trie. And can resolve it to "a1" .
But i have to store correct version of each word at last node that will increase the memory foot print .
Since i have all words loaded in to trie [correct/incorrect].
Is there any way i can make association between correct and incorrect word without again storing entire word in last node as value ?
Any pointer ?
public class TrieNode<T> {
private Map<Character, TrieNode<T>> childs;
private boolean complete;
private T value;
....
}

Answer 1

You could use a single dictionary for this. In C#, that would be:
Dictionary<string, string> MisspellingsLookup = new Dictionary<string, int>();
The key is the misspelling, and the value is the correct spelling.
Now, some words are commonly misspelled in multiple ways. For example, "occasion" is often misspelled as "ocassion" or "occassion" If you want to reduce the memory used by the multiple misspellings, you can use a temporary dictionary during construction. Whenever you add a misspelling, you look up the correct spelling in the good words dictionary, and if it's already there then you use that value. So all you do is store a reference to an existing word rather than creating a new string. Here's an example:
Dictionary<string, string> GoodWords = new Dictionary<string, int>();
Dictionary<string, string> Misspellings = new Dictionary<string, string>();
void AddMisspelling(string misspelled, string correct)
{
string goodWord;
if (!GoodWords.TryGetValue(correct, out goodWord))
{
goodWord = correct;
GoodWords.Add(correct, correct);
}
// Always use goodWord here, so you're not creating duplicate strings.
Misspellings.Add(misspelled, goodWord);
}
When you're done adding words, you can clear the GoodWords dictionary to save space:
GoodWords = null;
I recommend a dictionary here because it'll almost certainly use less memory, and lookup is O(1) rather than O(word length).