LeetCode - Unique Word Abbreviation

UniqueWordAbbreviation.java

// An abbreviation of a word follows the form <first letter><number><last letter>. Below are some examples of word abbreviations:

// a) it                      --> it    (no abbreviation)

//      1
// b) d|o|g                   --> d1g

//               1    1  1
//      1---5----0----5--8
// c) i|nternationalizatio|n  --> i18n

//               1
//      1---5----0
// d) l|ocalizatio|n          --> l10n
// Assume you have a dictionary and given a word, find whether its abbreviation is unique in the dictionary. A word's abbreviation is unique if no other word from the dictionary has the same abbreviation.

// Example: 
// Given dictionary = [ "deer", "door", "cake", "card" ]

// isUnique("dear") -> false
// isUnique("cart") -> true
// isUnique("cane") -> false
// isUnique("make") -> true

public class ValidWordAbbr {
    private Map<String, Integer> map;
    private Map<String, Integer> dict;

    public ValidWordAbbr(String[] dictionary) {
        map = new HashMap<String, Integer>();
        dict = new HashMap<String, Integer>();
        
        for(String word : dictionary){
            String key = abbreviate(word);
            if(!map.containsKey(key)){
                map.put(key, 0);
            }
            map.put(key, map.get(key) + 1);
            
            if(!dict.containsKey(word)){
                dict.put(word, 0);
            }
            dict.put(word, dict.get(word) + 1);
        }
    }
    
    private String abbreviate(String word){
        if(word == null || word.length() < 3) return word;
        int len = word.length() - 2;
        StringBuilder sb = new StringBuilder();
        sb.append(word.charAt(0));
        sb.append(len);
        sb.append(word.charAt(len + 1));
        return sb.toString();
    }

    public boolean isUnique(String word) {
        if(word == null) return false;
        String key = abbreviate(word);
        if(!dict.containsKey(word)){
            if(map.containsKey(key)) return false;
            else return true;
        } else{
            return map.get(key) == dict.get(word);
        }
    }
}


// Your ValidWordAbbr object will be instantiated and called as such:
// ValidWordAbbr vwa = new ValidWordAbbr(dictionary);
// vwa.isUnique("Word");
// vwa.isUnique("anotherWord");

// https://leetcode.com/discuss/86526/let-me-explain-the-question-with-better-examples

// better solution https://leetcode.com/discuss/71652/java-solution-with-hashmap-string-string-beats-submissions