sbool gLongestPrefixMatchNeqIdx_debug;

static int gLongestPrefixMatchNeqIdx(S line) {
  line = line.toLowerCase();
  if (gLongestPrefixMatchNeqIdx_debug)
    print("line=" + line);
  L<S> log = gLog();
  int best = -1, bestIdx = -1;
  for (int i = l(log)-1; i >= 0; i--) {
    S s = log.get(i).toLowerCase();
    continue if eq(s, line);
    int n = l(commonPrefix(s, line));
    if (gLongestPrefixMatchNeqIdx_debug)
      print("i=" + i + ", n=" + n + ", line=" + quote(log.get(i)));
    if (n > best) {
      bestIdx = i;
      best = n;
    }
  }
  ret bestIdx;
}