This is afollow upofShortest Word Distance. The only difference is now you are given the list of words and your method will be called_repeatedly_many times with different parameters. How would you optimize it?

Design a class which receives a list of words in the constructor, and implements a method that takes two words_word1_and_word2_and return the shortest distance between these two words in the list.

For example,
Assume that words =["practice", "makes", "perfect", "coding", "makes"].

Givenword1=“coding”,word2=“practice”, return 3.
Givenword1="makes",word2="coding", return 1.

Note:
You may assume thatword1does not equal toword2, and_word1_and_word2_are both in the list.

class WordDistance {

    Map<String, List<Integer>> hash;
    public WordDistance(String[] words) {
        hash = new HashMap<>();

        for (int i = 0; i < words.length; i++){
            if (hash.containsKey(words[i])){
                hash.get(words[i]).add(i);
            }
            else{
                List<Integer> list = new ArrayList<>();
                list.add(i);
                hash.put(words[i], list);
            }
        }
    }

    public int shortest(String word1, String word2) {
        int ans = Integer.MAX_VALUE;

        List<Integer> list1 = hash.get(word1);
        List<Integer> list2 = hash.get(word2);

        for (int i = 0, j = 0; i < list1.size() && j < list2.size(); ){
            if (list1.get(i) < list2.get(j)){
                ans = Math.min(ans, list2.get(j) - list1.get(i));
                i++;
            }
            else{
                ans = Math.min(ans, list1.get(i) - list2.get(j));
                j++;
            }
        }

        return ans;
    }
}

/**
 * Your WordDistance object will be instantiated and called as such:
 * WordDistance obj = new WordDistance(words);
 * int param_1 = obj.shortest(word1,word2);
 */