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+<title>Day 24 - Advent of Code 2016</title>
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+Oh, hello! Funny seeing you here.
+
+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.
+
+The puzzles probably took the longest; the easiest ones were around 45 minutes
+each, but the harder ones took 2-3 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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+-->
+<body>
+<header><div><h1 class="title-global"><a href="/">Advent of Code</a></h1><nav><ul><li><a href="/2016/about">[About]</a></li><li><a href="/2016/support">[AoC++]</a></li><li><a href="/2016/events">[Events]</a></li><li><a href="/2016/settings">[Settings]</a></li><li><a href="/2016/auth/logout">[Log Out]</a></li></ul></nav><div class="user">Neil Smith <span class="supporter">(AoC++)</span> <span class="star-count">48*</span></div></div><div><h1 class="title-event"> <span class="title-event-wrap">int y=</span><a href="/2016">2016</a><span class="title-event-wrap">;</span></h1><nav><ul><li><a href="/2016">[Calendar]</a></li><li><a href="/2016/leaderboard">[Leaderboard]</a></li><li><a href="/2016/stats">[Stats]</a></li><li><a href="/2016/sponsors">[Sponsors]</a></li></ul></nav></div></header>
+
+<div id="sidebar">
+<div id="sponsor"><div class="quiet">Our <a href="/2016/sponsors">sponsors</a> help make AoC possible:</div><p><a href="https://info.esparklearning.com/join-our-team-full-stack-engineer" target="_blank" onclick="if(ga)ga('send','event','sponsor','click',this.href);">eSpark Learning</a> - Solve the greatest puzzle of our day - transform education</p></div>
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+
+<main>
+<article class="day-desc"><h2>--- Day 24: Air Duct Spelunking ---</h2><p>You've finally met your match; the doors that provide access to the roof are locked tight, and all of the controls and related electronics are inaccessible. You simply can't reach them.</p>
+<p>The robot that cleans the air ducts, however, <em>can</em>.</p>
+<p>It's not a very fast <span title="The Brave Little Air Duct Cleaning Robot That Could">little robot</span>, but you reconfigure it to be able to interface with some of the exposed wires that have been routed through the <a href="https://en.wikipedia.org/wiki/HVAC">HVAC</a> system. If you can direct it to each of those locations, you should be able to bypass the security controls.</p>
+<p>You extract the duct layout for this area from some blueprints you acquired and create a map with the relevant locations marked (your puzzle input). <code>0</code> is your current location, from which the cleaning robot embarks; the other numbers are (in <em>no particular order</em>) the locations the robot needs to visit at least once each. Walls are marked as <code>#</code>, and open passages are marked as <code>.</code>. Numbers behave like open passages.</p>
+<p>For example, suppose you have a map like the following:</p>
+<pre><code>###########
+#0.1.....2#
+#.#######.#
+#4.......3#
+###########
+</code></pre>
+<p>To reach all of the points of interest as quickly as possible, you would have the robot take the following path:</p>
+<ul>
+<li><code>0</code> to <code>4</code> (<code>2</code> steps)</li>
+<li><code>4</code> to <code>1</code> (<code>4</code> steps; it can't move diagonally)</li>
+<li><code>1</code> to <code>2</code> (<code>6</code> steps)</li>
+<li><code>2</code> to <code>3</code> (<code>2</code> steps)</li>
+</ul>
+<p>Since the robot isn't very fast, you need to find it the <em>shortest route</em>. This path is the fewest steps (in the above example, a total of <code>14</code>) required to start at <code>0</code> and then visit every other location at least once.</p>
+<p>Given your actual map, and starting from location <code>0</code>, what is the <em>fewest number of steps</em> required to visit every non-<code>0</code> number marked on the map at least once?</p>
+</article>
+<p>Your puzzle answer was <code>412</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>Of course, if you leave the cleaning robot somewhere weird, someone is bound to notice.</p>
+<p>What is the fewest number of steps required to start at <code>0</code>, visit every non-<code>0</code> number marked on the map at least once, and then <em>return to <code>0</code></em>?</p>
+</article>
+<p>Your puzzle answer was <code>664</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="/2016">return to your advent calendar</a> and try another puzzle.</p>
+<p>If you still want to see it, you can <a href="24/input" target="_blank">get your puzzle input</a>.</p>
+<p>You can also <span class="share">[Share<span class="share-content">on
+ <a href="https://twitter.com/intent/tweet?text=I%27ve+completed+%22Air+Duct+Spelunking%22+%2D+Day+24+%2D+Advent+of+Code+2016&url=http%3A%2F%2Fadventofcode%2Ecom%2F2016%2Fday%2F24&related=ericwastl&hashtags=AdventOfCode" target="_blank">Twitter</a>
+ <a href="https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2F2016%2Fday%2F24" target="_blank">Google+</a>
+ <a href="http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2F2016%2Fday%2F24&title=I%27ve+completed+%22Air+Duct+Spelunking%22+%2D+Day+24+%2D+Advent+of+Code+2016" target="_blank">Reddit</a
+></span>]</span> this puzzle.</p>
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