288. Unique Word Abbreviation

class ValidWordAbbr {

    Set<String> set = new HashSet<>();
    Map<String, Integer> map = new HashMap<>();

    public ValidWordAbbr(String[] dictionary) {
        for(String w : dictionary)
        {
            if(set.contains(w)) continue;
            String str = shorten(w);
            set.add(w);
            map.put(str, map.getOrDefault(str, 0) + 1);
        }
    }

    String shorten(String str)
    {
        int n = str.length();
        if(n < 3) return str;
        return "" + str.charAt(0) + (n - 2) + str.charAt(n - 1);
    }

    public boolean isUnique(String word) {
        String str = shorten(word);
        if(set.contains(word) && map.get(str) < 2) return true;
        if(!set.contains(word) && !map.containsKey(str)) return true;
        return false;
    }
}

/**
 * Your ValidWordAbbr object will be instantiated and called as such:
 * ValidWordAbbr obj = new ValidWordAbbr(dictionary);
 * boolean param_1 = obj.isUnique(word);
 */