<meta charset="UTF-8">

<meta name="viewport" content="width=device-width, initial-scale=1.0">

<title>{% if page.title %}{{ page.title }} - {{ site.title }}{% else %}{{ site.title }}{% endif %}</title>

<meta name="author" content="{{ site.author }}">

<meta name="description" content="{% if page.title %}{{ page.title }}{% else %}{{ site.title }}{% endif %}">

<meta name="keywords" content="{% if page.tags.size > 0 %}{% for tag in page.tags %}{{ tag }}{% if forloop.last == false %}, {% endif %}{% endfor %}{% endif %}">

<!-- Open Graph -->

<meta property="og:title" content="{% if page.title %}{{ page.title }} - {{ site.title }}{% else %}{{ site.title }}{% endif %}">

<meta property="og:type" content="website">

<meta property="og:url" content="{{ page.url | prepend: site.url }}">

<meta property="og:description" content="{{ site.description }}">

<meta property="og:site_name" content="{{ site.title }}">

<link rel="stylesheet" href="//cdn.staticfile.org/normalize/6.0.0/normalize.min.css">

<link rel="stylesheet" href="//at.alicdn.com/t/font_roc50gemkxpw4s4i.css">

<link rel="stylesheet" href="/assets/css/github-markdown.css">

<link rel="stylesheet" href="/assets/css/prism.css">

<link rel="stylesheet" href="/assets/css/share.min.css">

<link rel="stylesheet" href="/assets/css/app.min.css">

<link rel="stylesheet" href="https://cdn.bootcss.com/font-awesome/4.7.0/css/font-awesome.min.css">

<script src="https://cdn.staticfile.org/jquery/3.2.1/jquery.min.js"></script>

{% if site.mathjax %}

{% include mathjax.html %}

{% endif %}

{% include anchor.html %}