sclass SuperPrecise {

  sclass C {

    char c;

    bool output;

    *() {}

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

  }

  S poemID;

  new L<C> script;

  int i = 0;

  bool fail;

  new StringBuilder out;

  *(S *poemID) {

    for (E e : parsePoem(poemID)) {

      if (e.q != null)

        addInput(e.q + "\n");

      else if (e.a != null)

        addOutput(e.a + "\n");

    }

    loop();

  }

  // probably remove this

  void loop() {

    printOut();

    S line;

    while ((line = readLine()) != null) {

      for (char c : chars(line + "\n"))

        onIncomingCharacter(c);

      printOut();

    }

  }

  void addOutput(S text) {

    for (char c : asChars(text))

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

  }

  void addInput(S text) {

    for (char c : asChars(text))

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

  }

  void onIncomingCharacter(char c) {

    if (fail || get(script, i) == null)

      charPut('?');

    else {

      C x = get(script, i);

      assertFalse(x.output);

      if (c == x.c) {

        ++i;

        printOut();

      } else {

        fail = true;

        charPut('?');

      }

    }

  }

  void printOut() {

    while (!fail && get(script, i) != null && get(script, i).output)

      charPut(get(script, i++).c);

    //charPut_flush();

  }

  void charPut(char c) {

    out.append(c);

  }

}