288. Unique Word Abbreviation

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

Solution

(1) Java

class ValidWordAbbr {

    private Map<String, String> map = new HashMap<>();

    public ValidWordAbbr(String[] dictionary) {
        for(String str : dictionary) {
            if(str.length() < 3) {
                map.put(str, str);
            } else {
                String key = getKey(str);
                if (map.containsKey(key)) {
                    map.put(key, "");
                } else {
                    map.put(key, str);
                }
            }
        }
    }

    public boolean isUnique(String word) {
        String key = word;
        if (word.length() >= 3) {
            key = getKey(word);
        }
        return !map.containsKey(key) || map.get(key).equals(word);
    }

    private String getKey(String str) {
        StringBuilder sb = new StringBuilder();
        sb.append(str.charAt(0)).append(str.length()-2).append(str.charAt(str.length()-1));
        return sb.toString();
    }
}

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

(2) Python

class ValidWordAbbr:

    def __init__(self, dictionary):
        """
        :type dictionary: List[str]
        """
        self.abdict = collections.defaultdict(set)
        for string in dictionary:
            if len(string) < 3:
                self.abdict[string].add(string)
            else:
                sub = string[0]+str(len(string)-2)+string[-1]
                self.abdict[sub].add(string)


    def isUnique(self, word):
        """
        :type word: str
        :rtype: bool
        """
        sub = word
        if len(word) >= 3: 
            sub = word[0]+str(len(word)-2)+word[-1]
        if not word in self.abdict[sub] and len(self.abdict[sub])==0:
            return True
        if word in self.abdict[sub] and len(self.abdict[sub])==1:
            return True
        return False



# Your ValidWordAbbr object will be instantiated and called as such:
# obj = ValidWordAbbr(dictionary)
# param_1 = obj.isUnique(word)

(3) Scala