🎄⌨️ Advent of Code 2018

<h2>Wiki Formatting Rule Summary</h2>

  #  Blank lines are paragraph breaks
  #  Bullets are "*" surrounded by two spaces at the beginning of a line
  #  Enumeration items are "#" or a digit and a "." surrounded by two
     spaces at the beginning of a line
  #  Indented paragraphs begin with a tab or two spaces
  #  Hyperlinks are contained within square brackets:
     <nowiki>"<b>[</b><i>target</i><b>]</b>"
     or "<b>[</b><i>target</i><b>|</b><i>label</i><b>]</b>"</nowiki>
  #  Most ordinary HTML works
  #  &lt;verbatim&gt; and &lt;nowiki&gt;

We call the first five rules above the "wiki" formatting rules.
The last two rules are the HTML formatting rules.

<h2>Formatting Rule Details</h2>

  1.  <b>Paragraphs.</b>
      Any sequence of one or more blank lines forms a paragraph break.
      Centered or right-justified paragraphs are not supported by wiki markup,
      but you can do these things if you need them using HTML.

  2.  <b>Bullet Lists.</b>
      A bullet list item is a line that begins with a single "*" character
      surrounded on both sides by two or more spaces or by a tab.
      Only a single level of bullet list is supported by wiki.
      For nested lists, use HTML.

  3.  <b>Enumeration Lists.</b>
      An enumeration list item is a line that begins with a single "#"
      character surrounded on both sides by two or more spaces or by a tab.
      Or it can be a number and a "." (ex:  "5.") surrounded on both sides
      by two spaces or a tab.
      Only a single level of enumeration list is supported by wiki.
      For nested lists or for enumerations that count using letters or
      roman numerals, use HTML.

  4.  <b>Indented Paragraphs.</b>
      Any paragraph that begins with two or more spaces or a tab and which
      is not a bullet or enumeration list item is rendered indented.
      Only a single level of indentation is supported by wiki.
      Use HTML for deeper indentation.

  5.  <b>Hyperlinks.</b>
      Text within square brackets <nowiki>("[...]")</nowiki> becomes a
      hyperlink. The target can be a wiki page name, the artifact ID of
      a check-in or ticket, the name of an image, a URL, or an
      [#intermap|interwiki link] of the form 
      "<i>Tag</i><b>:</b><i>PageName</i>".
      By default, the target is displayed as the text of the hyperlink.
      But you can specify alternative text after the target name
      separated by a "|" character.
      You can also link to internal anchor names using 
      <nowiki>[#anchor-name],</nowiki> providing you have added the necessary 
      "&lt;a name='anchor-name'&gt;&lt;/a&gt;" tag to your wiki page.

  6.  <b>HTML.</b>
      The following standard HTML elements may be used:
      &lt;a&gt; &lt;address&gt; &lt;article&gt; &lt;aside&gt; &lt;b&gt;
      &lt;big&gt; &lt;blockquote&gt; &lt;br&gt; &lt;center&gt; &lt;cite&gt;
      &lt;code&gt; &lt;col&gt; &lt;colgroup&gt; &lt;dd&gt; 
      &lt;del&gt; &lt;dfn&gt;
      &lt;div&gt; &lt;dl&gt; &lt;dt&gt; &lt;em&gt; &lt;font&gt; &lt;footer&gt;
      &lt;ins&gt;
      &lt;h1&gt; &lt;h2&gt; &lt;h3&gt; &lt;h4&gt; &lt;h5&gt; &lt;h6&gt;
      &lt;header&gt; &lt;hr&gt; &lt;i&gt; &lt;img&gt; &lt;kbd&gt; &lt;li&gt;
      &lt;nav&gt; &lt;nobr&gt; &lt;nowiki&gt; &lt;ol&gt; &lt;p&gt; &lt;pre&gt;
      &lt;s&gt; &lt;samp&gt; &lt;section&gt; &lt;small&gt; &lt;span&gt;
      &lt;strike&gt; &lt;strong&gt; &lt;sub&gt; &lt;sup&gt; &lt;table&gt;
      &lt;tbody&gt; &lt;td&gt; &lt;tfoot&gt; &lt;th&gt; &lt;thead&gt;
      &lt;title&gt; &lt;tr&gt; &lt;tt&gt; &lt;u&gt; &lt;ul&gt; &lt;var&gt;
      &lt;verbatim&gt;. There are two non-standard elements available:
      &lt;verbatim&gt; and &lt;nowiki&gt;. No other elements are allowed.
      All attributes are checked and only a few benign attributes are
      allowed on each element. In particular, any attributes that specify
      javascript or CSS are elided.

  7.  <b>Special Markup.</b>
      The &lt;nowiki&gt; tag disables all wiki formatting rules through
      the matching &lt;/nowiki&gt; element. The &lt;verbatim&gt; tag works
      like &lt;pre&gt; with the addition that it also disables all wiki
      and HTML markup through the matching &lt;/verbatim&gt;.
      Text within 
      <tt>&lt;verbatim&nbsp;type="pikchr"&gt;...&lt;/verbatim&gt;</tt>
      is formatted using <a href="https://pikchr.org/home">Pikchr</a>.


<a name="intermap"></a>
<h2>Interwiki Tag [/intermap|Map]</h2>
<i>None</i></blockquote>