Easy
跟Shortest Word Distance iii差不多，更简单少了处理word1, word2相同那部分.

class Solution {
    public int shortestDistance(String[] words, String word1, String word2) {
        int index1 = words.length;
        int index2 = -words.length;
        int shortest = words.length;
        for (int i = 0; i < words.length; i++){
            if (words[i].equals(word1)){
                index1 = i;
            } else if (words[i].equals(word2)){
                index2 = i;
            }
            shortest = Math.min(shortest, Math.abs(index1 - index2));
        }
        return shortest;
    }
}