i searched the web for an implementation of a levenshtein trie and 
i found this: [Levenshtein Distance Challenge: Causes](http://www.royvanrijn.com/blog/2012/02/levenshtein-distance-challenge-causes/comment-page-1/#comment-6945). 
i tried to add a piece of code to normalize the words. If a word
for example has 5 letters ('Apple') and i have this word ('Aple')
the distance is 1 and i accept it as the same. When i for example
have a much longer word ('circumstances') you can make more mistakes.
If you have two mistakes in this word the original code would 
calculate the minimum distance to be 2 and wont accept it. So i want
to use a logarithm. With the logarithm the distance between 'circumstances'
and 'kirkumstances' would be smaller than 2 and because of the cast
to int it would be 1. Thats what i want to do.

```
public class LevenshteinTrie {
    private int distance = -1;
    private Trie trie = null;

    public LevenshteinTrie(int distance, Set<String> words) {
        this.distance = distance;
        this.trie = new Trie();

        for(String word : words) {
            this.trie.insert(word);
        }
    }

    public Set<String> discoverFriends(String word, boolean normalized) {
        Set<String> results = new HashSet<String>();

        int[] currentRow = new int[word.length() + 1];

        List<Character> chars = new ArrayList<Character>(word.length());

        for(int i = 0; i < word.length(); i++) {
            chars.add(word.charAt(i));
            currentRow[i] = i;
        }

        currentRow[word.length()] = word.length();

        for(Character c : this.trie.getRoot().getChildren().keySet()) {
            this.traverseTrie(this.trie.getRoot().getChildren().get(c), c, chars, currentRow, results, normalized);
        }

        return results;
    }

    private void traverseTrie(TrieNode node, char letter, List<Character> word, int[] previousRow, Set<String> results, boolean normalized) {
        int size = previousRow.length;
        int[] currentRow = new int[size];

        currentRow[0] = previousRow[0] + 1;

        int minimumElement = currentRow[0];

        int insertCost = 0;
        int deleteCost = 0; 
        int replaceCost = 0;

        for(int i = 1; i < size; i++) {
            insertCost = currentRow[i - 1] + 1;
            deleteCost = previousRow[i] + 1;

            if(word.get(i - 1) == letter) {
                replaceCost = previousRow[i - 1];
            } else {
                replaceCost = previousRow[i - 1] + 1;
            }

            currentRow[i] = Math.min(Math.min(insertCost, deleteCost), replaceCost);

            if(currentRow[i] < minimumElement) {
                if(normalized) {
                    minimumElement = (int)(currentRow[i] / (Math.log10(word.size())));
                } else {
                    minimumElement = currentRow[i];
                }
            }
        }

        int tempCurrentRow = currentRow[size - 1];

        if(normalized) {
            tempCurrentRow = (int)(currentRow[size - 1] / (Math.log10(word.size())));
        }

        System.out.println(tempCurrentRow);

        if(tempCurrentRow <= this.distance && node.getWord() != null) {
            results.add(node.getWord());
        }

        if(minimumElement <= this.distance) {
            for(Character c : node.getChildren().keySet()) {
                this.traverseTrie(node.getChildren().get(c), c, word, currentRow, results, normalized);
            }
        }
    }
}

public class Trie {
    private TrieNode root = null;;

    public Trie() {
        this.root = new TrieNode();
    }

    public void insert(String word) {
        TrieNode current = this.root;

        if (word.length() == 0) {
            current.setWord(word);
        }

        for (int i = 0; i < word.length(); i++) {
            char letter = word.charAt(i);

            TrieNode child = current.getChild(letter);

            if (child != null) {
                current = child;
            } else {
                current.getChildren().put(letter, new TrieNode());
                current = current.getChild(letter);
            }

            if (i == word.length() - 1) {
                current.setWord(word);
            }
        }
    }
 }

public class TrieNode {
    public static final int ALPHABET = 26;
    private String word = null;
    private Map<Character, TrieNode> children = null;

    public TrieNode() {
        this.word = null;
        this.children = new HashMap<Character, TrieNode>(ALPHABET);
    }

    public TrieNode getChild(char letter) {
        if(this.children != null) {
            if(children.containsKey(letter)) {
                return children.get(letter);
            }
        }

        return null;
    }

    public String getWord() {
        return word;
    }
}

```

Unfortunately this code does not work correctly. I set the maximum distance to 1.
When i now run the program and search for 'vdimir putin' (i have 'vladimir putin'
in my trie) the program wont accept it as a friend. When i print out the temporary
calculated distances it looks like that:

The tempCurrentRows when maximum distance = 1:

```
11
11
10
10
10
10
11
11
11
11
10
11
11
11
11
11
11
11
10
10
10
10
10
10
10
10
10
10
9
11
11
10
10
10
10

```

But when i set the maximum distance to 2 the temporary distances are changing:

The tempCurrentRows when maximum distance = 2:

```
11
11
11
10
10
10
10
9
9
8
7
6
5
4
3
2
1
11
11
10
10
9
9

```

So there must be a huge mistake in the code. But i dont get where and why
and how i have to change the code to work as i want it to work.