include_c "string.h";
use "sequence_queries.g";
use "iterator_models.g";
use "slist.g";

fun main() -> int@ {
  let str = "yabadabado";
  let l = @slist<char>();
  let i = strlen(str) - 1;
  while (i >= 0) {
    push_front(str[i], l);
    --i;
  }
  let seq = begin(l);
  let seq_end = end(l);

  /* ba */
  let subseq = begin(l);
  advance(subseq, 2);
  let subseq_end = begin(l);
  advance(subseq_end, 4);

  let i = find_last_subsequence(seq, seq_end, subseq, subseq_end);
  let d = distance(seq, i);
  if (not distance(seq, i) == 6)
    return -1;

  let i = find_last_subsequence(seq, seq_end, subseq, subseq_end,
				fun (char a, char b): a == b);
  if (not distance(seq, i) == 6)
    return -1;

  return 0;
}