class Solution {
    public String reverseWords(String s) {
        StringBuilder sb = new StringBuilder();

        String wordSoFar = "";
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == ' ') {
                sb.append(wordSoFar);
                sb.append(s.charAt(i));
                wordSoFar = "";
            }
            else {
                wordSoFar = s.charAt(i) + wordSoFar;
            }
        }
        if (wordSoFar.length() > 0) {
            sb.append(wordSoFar);
        }

        return sb.toString();
    }
}