def get_lcof_questions():
    """获取剑指Offer题目"""
    resp = fetch(url=lcof_problems_url, headers=async_headers)
    if resp is None:
        return None
    res = resp.json()
    questions = res['stat_status_pairs']
    for question in questions:
        fe_qid = question['stat']['frontend_question_id']
        qno = fe_qid.replace('面试题', '').strip()
        title = question['stat']['question__title'].replace(' LCOF', '').strip()
        link = problems_url + question['stat']['question__title_slug']
        git_link = '/lcof/{}/README.md'.format(quote(fe_qid + '. ' + title))
        col1 = '[{}]({})'.format(qno, link)
        col2 = '[{}]({})'.format(title, git_link)
        col3 = difficulties.get(str(question['difficulty']['level']))
        yield [col1, col2, col3]
def get_all_questions():
    """获取所有题目"""
    cn_res = get_cn_questions()
    resp = fetch(url=all_problems_url, headers=async_headers)
    if resp is None:
        return
    res = resp.json()
    questions = res['stat_status_pairs']

    for question in questions:
        qid = str(question['stat']['question_id']).zfill(4)
        title = question['stat']['question__title']
        link = problems_url + question['stat']['question__title_slug']
        git_link = '/solution/{}/README.md'.format(qid + '.' + quote(title))
        cn_title = cn_res.get(qid) or title
        col1 = '[{}]({})'.format(qid, link)
        col2 = '[{}]({})'.format(cn_title, git_link)
        col3 = difficulties.get(str(question['difficulty']['level']))
        yield [col1, col2, col3]