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+Oh, hello! Funny seeing you here.
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+I appreciate your enthusiasm, but you aren't going to find much down here.
+There certainly aren't clues to any of the puzzles. The best surprises don't
+even appear in the source until you unlock them for real.
+
+Please be careful with automated requests; I'm not Google, and I can only take
+so much traffic. Please be considerate so that everyone gets to play.
+
+If you're curious about how Advent of Code works, it's running on some custom
+Perl code. Other than a few integrations (auth, analytics, ads, social media),
+I built the whole thing myself, including the design, animations, prose, and
+all of the puzzles.
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+The puzzles probably took the longest; the easiest ones took an hour or two
+each, but the harder ones took 4-5 hours, and a few even longer than that. A
+lot of effort went into building this thing - I hope you're enjoying playing it
+as much as I enjoyed making it for you!
+
+If you'd like to hang out, I'm @ericwastl on Twitter.
+
+- Eric Wastl
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+<header><div><h1 class="title-global"><a href="/">Advent of Code</a></h1><nav><ul><li><a href="/2017/about">[About]</a></li><li><a href="/2017/support">[AoC++]</a></li><li><a href="/2017/events">[Events]</a></li><li><a href="/2017/settings">[Settings]</a></li><li><a href="/2017/auth/logout">[Log Out]</a></li></ul></nav><div class="user">Neil Smith <span class="supporter">(AoC++)</span> <span class="star-count">44*</span></div></div><div><h1 class="title-event"> <span class="title-event-wrap">0xffff&</span><a href="/2017">2017</a><span class="title-event-wrap"></span></h1><nav><ul><li><a href="/2017">[Calendar]</a></li><li><a href="/2017/leaderboard">[Leaderboard]</a></li><li><a href="/2017/stats">[Stats]</a></li><li><a href="/2017/sponsors">[Sponsors]</a></li></ul></nav></div></header>
+
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+<div id="sponsor"><div class="quiet">Our <a href="/2017/sponsors">sponsors</a> help make Advent of Code possible:</div><p><a href="http://www.novetta.com/careers?utm_campaign=Advent%20of%20Code%202017&utm_source=www.adventofcode.com&utm_medium=ad" target="_blank" onclick="if(ga)ga('send','event','sponsor','click',this.href);" rel="noopener">Novetta</a> - Unleash your imagination. Innovate at Novetta.</p></div>
+<p class="quiet">By popular demand, there are now AoC-themed objects available (until Jan. 3rd)! Get them shipped <a href="https://teespring.com/advent-of-code" target="_blank">from the US</a> or <a href="https://teespring.com/advent-of-code-eu" target="_blank">from Europe</a>.</p>
+
+</div><!--/sidebar-->
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+<main>
+<article class="day-desc"><h2>--- Day 22: Sporifica Virus ---</h2><p>Diagnostics indicate that the local <em>grid computing cluster</em> has been contaminated with the <em>Sporifica Virus</em>. The grid computing cluster is a seemingly-<span title="The infinite is possible at AdventOfCodeCom.">infinite</span> two-dimensional grid of compute nodes. Each node is either <em>clean</em> or <em>infected</em> by the virus.<p>
+<p>To <a href="https://en.wikipedia.org/wiki/Morris_worm#The_mistake">prevent overloading</a> the nodes (which would render them useless to the virus) or detection by system administrators, exactly one <em>virus carrier</em> moves through the network, infecting or cleaning nodes as it moves. The virus carrier is always located on a single node in the network (the <em>current node</em>) and keeps track of the <em>direction</em> it is facing.</p>
+<p>To avoid detection, the virus carrier works in bursts; in each burst, it <em>wakes up</em>, does some <em>work</em>, and goes back to <em>sleep</em>. The following steps are all executed <em>in order</em> one time each burst:</p>
+<ul>
+<li>If the <em>current node</em> is <em>infected</em>, it turns to its <em>right</em>. Otherwise, it turns to its <em>left</em>. (Turning is done in-place; the <em>current node</em> does not change.)</li>
+<li>If the <em>current node</em> is <em>clean</em>, it becomes <em>infected</em>. Otherwise, it becomes <em>cleaned</em>. (This is done <em>after</em> the node is considered for the purposes of changing direction.)</li>
+<li>The virus carrier <a href="https://www.youtube.com/watch?v=2vj37yeQQHg">moves</a> <em>forward</em> one node in the direction it is facing.</li>
+</ul>
+<p>Diagnostics have also provided a <em>map of the node infection status</em> (your puzzle input). <em>Clean</em> nodes are shown as <code>.</code>; <em>infected</em> nodes are shown as <code>#</code>. This map only shows the center of the grid; there are many more nodes beyond those shown, but none of them are currently infected.</p>
+<p>The virus carrier begins in the middle of the map facing <em>up</em>.</p>
+<p>For example, suppose you are given a map like this:</p>
+<pre><code>..#
+#..
+...
+</code></pre>
+<p>Then, the middle of the infinite grid looks like this, with the virus carrier's position marked with <code>[ ]</code>:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . # . . .
+. . . #[.]. . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>The virus carrier is on a <em>clean</em> node, so it turns <em>left</em>, <em>infects</em> the node, and moves left:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . # . . .
+. . .[#]# . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>The virus carrier is on an <em>infected</em> node, so it turns <em>right</em>, <em>cleans</em> the node, and moves up:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . .[.]. # . . .
+. . . . # . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>Four times in a row, the virus carrier finds a <em>clean</em>, <em>infects</em> it, turns <em>left</em>, and moves forward, ending in the same place and still facing up:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . #[#]. # . . .
+. . # # # . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>Now on the same node as before, it sees an infection, which causes it to turn <em>right</em>, <em>clean</em> the node, and move forward:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . # .[.]# . . .
+. . # # # . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>After the above actions, a total of <code>7</code> bursts of activity had taken place. Of them, <code>5</code> bursts of activity caused an infection.</p>
+<p>After a total of <code>70</code>, the grid looks like this, with the virus carrier facing up:</p>
+<pre><code>. . . . . # # . .
+. . . . # . . # .
+. . . # . . . . #
+. . # . #[.]. . #
+. . # . # . . # .
+. . . . . # # . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>By this time, <code>41</code> bursts of activity caused an infection (though most of those nodes have since been cleaned).</p>
+<p>After a total of <code>10000</code> bursts of activity, <code>5587</code> bursts will have caused an infection.</p>
+<p>Given your actual map, after <code>10000</code> bursts of activity, <em>how many bursts cause a node to become infected</em>? (Do not count nodes that begin infected.)</p>
+</article>
+<p>Your puzzle answer was <code>5182</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>As you go to remove the virus from the infected nodes, it <em>evolves</em> to resist your attempt.</p>
+<p>Now, before it infects a clean node, it will <em>weaken</em> it to disable your defenses. If it encounters an infected node, it will instead <em>flag</em> the node to be cleaned in the future. So:</p>
+<ul>
+<li><em>Clean</em> nodes become <em>weakened</em>.</li>
+<li><em>Weakened</em> nodes become <em>infected</em>.</li>
+<li><em>Infected</em> nodes become <em>flagged</em>.</li>
+<li><em>Flagged</em> nodes become <em>clean</em>.</li>
+</ul>
+<p>Every node is always in exactly one of the above states.</p>
+<p>The virus carrier still functions in a similar way, but now uses the following logic during its bursts of action:</p>
+<ul>
+<li>Decide which way to turn based on the <em>current node</em>:
+ <ul>
+ <li>If it is <em>clean</em>, it turns <em>left</em>.</li>
+ <li>If it is <em>weakened</em>, it does <em>not</em> turn, and will continue moving in the same direction.</li>
+ <li>If it is <em>infected</em>, it turns <em>right</em>.</li>
+ <li>If it is <em>flagged</em>, it <em>reverses</em> direction, and will go back the way it came.</li>
+ </ul>
+</li>
+<li>Modify the state of the <em>current node</em>, as described above.</li>
+<li>The virus carrier moves <em>forward</em> one node in the direction it is facing.</li>
+</ul>
+<p>Start with the same map (still using <code>.</code> for <em>clean</em> and <code>#</code> for infected) and still with the virus carrier starting in the middle and facing <em>up</em>.</p>
+<p>Using the same initial state as the previous example, and drawing <em>weakened</em> as <code>W</code> and <em>flagged</em> as <code>F</code>, the middle of the infinite grid looks like this, with the virus carrier's position again marked with <code>[ ]</code>:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . # . . .
+. . . #[.]. . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>This is the same as before, since no initial nodes are <em>weakened</em> or <em>flagged</em>. The virus carrier is on a clean node, so it still turns left, instead <em>weakens</em> the node, and moves left:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . # . . .
+. . .[#]W . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>The virus carrier is on an infected node, so it still turns right, instead <em>flags</em> the node, and moves up:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . .[.]. # . . .
+. . . F W . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>This process repeats three more times, ending on the previously-flagged node and facing right:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . W W . # . . .
+. . W[F]W . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>Finding a flagged node, it reverses direction and <em>cleans</em> the node:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . W W . # . . .
+. .[W]. W . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>The <em>weakened</em> node becomes infected, and it continues in the same direction:</p>
+<pre><code>. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . W W . # . . .
+.[.]# . W . . . .
+. . . . . . . . .
+. . . . . . . . .
+. . . . . . . . .
+</code></pre>
+<p>Of the first <code>100</code> bursts, <code>26</code> will result in <em>infection</em>. Unfortunately, another feature of this evolved virus is <em>speed</em>; of the first <code>10000000</code> bursts, <code>2511944</code> will result in <em>infection</em>.</p>
+<p>Given your actual map, after <code>10000000</code> bursts of activity, <em>how many bursts cause a node to become infected</em>? (Do not count nodes that begin infected.)</p>
+</article>
+<p>Your puzzle answer was <code>2512008</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
+<p>At this point, you should <a href="/2017">return to your advent calendar</a> and try another puzzle.</p>
+<p>If you still want to see it, you can <a href="22/input" target="_blank">get your puzzle input</a>.</p>
+<p>You can also <span class="share">[Share<span class="share-content">on
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