sclass C {

  char c;

  bool output;

  *() {}

  *(char *c, bool *output) {}

  public bool equals(O o) {

    ret o instanceof C && c == ((C) o).c && output == ((C) o).output;

  }

  public int hashCode() {

    ret (int) c + (output ? 0x1000 : 0);

  }

}

static L<C> poemToC(S poemID) {

  new L<C> l;

  for (E e : parsePoem(poemID))

    if (e.q != null)

      addC(l, e.q + "\n", false);

    else if (e.a != null)

      addC(l, e.a + "\n", true);

  ret l;

}

static void addC(L<C> script, S s, bool output) {

  for (char c : asChars(s))

    script.add(new C(c, output));

}

static L<E> poemFromC(L<C> script) {

  new L<E> l;

  int i = 0;

  while (i < l(script)) {

    new E e;

    int j = poemFromC_scan(script, i, false);

    if (j > i)

      e.q = poemFromC_join(script, i, j);

    else {

      j = poemFromC_scan(script, i, true);

      assertTrue(j > i);

      e.a = poemFromC_join(script, i, j);

    }

    l.add(e);

    i = j;

  }

  ret l;

}

static int poemFromC_scan(L<C> script, int i, bool output) {

  while (i < l(script) && script.get(i).output == output)

    ++i;

  ret i;

}

static S poemFromC_join(L<C> script, int i, int j) {

  new StringBuilder buf;

  for (; i < j; i++)

    buf.append(script.get(i).c);

  ret str(buf);

}