static int feedbackScore(S s) {
  s = dropWords(s, "bot");
  s = dropPunctuation(s);
  L<S> tok = nlTok(s);
  if (l(tok) != 3) ret 0;
  S word = tok.get(1).toLowerCase();
  word = collapseWord(word);
  if (litlist("nice", "god" /* matches both "god" and "good" :) */, "ok", "corect", "right", "true", "yes", "col" /* cool */).contains(word))
    ret 1;
  if (litlist("no", "wrong", "bad").contains(word))
    ret -1;
  ret 0;
}