javahash1.java

static String firstRepeatedWord(String s) {
        HashSet<String> hashset = new HashSet<>();
        String[] splited = s.split("\\s+");
        for (String word : splited) {
            word = word.trim().replaceAll("\\W", "");
            if (hashset.contains(word)) {
                return word;
            } else {
                hashset.add(word);
            }
        }
        return "";
    }