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+<title>Day 12 - 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">24*</span></div></div><div><h1 class="title-event"> <span class="title-event-wrap">//</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 12: Leonardo's Monorail ---</h2><p>You finally reach the top floor of this building: a garden with a slanted glass ceiling. Looks like there are no more stars to be had.</p>
+<p>While sitting on a nearby bench amidst some <a href="https://www.google.com/search?q=tiger+lilies&tbm=isch">tiger lilies</a>, you manage to decrypt some of the files you extracted from the servers downstairs.</p>
+<p>According to these documents, Easter Bunny HQ isn't just this building - it's a collection of buildings in the nearby area. They're all connected by a local monorail, and there's another building not far from here! Unfortunately, being night, the monorail is currently not operating.</p>
+<p>You remotely connect to the monorail control systems and discover that the boot sequence expects a password. The password-checking logic (your puzzle input) is easy to extract, but the code it uses is strange: it's <span title="Strangely, this assembunny code doesn't seem to be very good at multiplying.">assembunny</span> code designed for the <a href="11">new computer</a> you just assembled. You'll have to execute the code and get the password.</p>
+<p>The assembunny code you've extracted operates on four <a href="https://en.wikipedia.org/wiki/Processor_register">registers</a> (<code>a</code>, <code>b</code>, <code>c</code>, and <code>d</code>) that start at <code>0</code> and can hold any <a href="https://en.wikipedia.org/wiki/Integer">integer</a>. However, it seems to make use of only a few <a href="https://en.wikipedia.org/wiki/Instruction_set">instructions</a>:</p>
+<ul>
+<li><code>cpy x y</code> <em>copies</em> <code>x</code> (either an integer or the <em>value</em> of a register) into register <code>y</code>.</li>
+<li><code>inc x</code> <em>increases</em> the value of register <code>x</code> by one.</li>
+<li><code>dec x</code> <em>decreases</em> the value of register <code>x</code> by one.</li>
+<li><code>jnz x y</code> <em>jumps</em> to an instruction <code>y</code> away (positive means forward; negative means backward), but only if <code>x</code> is <em>not zero</em>.</li>
+</ul>
+<p>The <code>jnz</code> instruction moves relative to itself: an offset of <code>-1</code> would continue at the previous instruction, while an offset of <code>2</code> would <em>skip over</em> the next instruction.</p>
+<p>For example:</p>
+<pre><code>cpy 41 a
+inc a
+inc a
+dec a
+jnz a 2
+dec a
+</code></pre>
+<p>The above code would set register <code>a</code> to <code>41</code>, increase its value by <code>2</code>, decrease its value by <code>1</code>, and then skip the last <code>dec a</code> (because <code>a</code> is not zero, so the <code>jnz a 2</code> skips it), leaving register <code>a</code> at <code>42</code>. When you move past the last instruction, the program halts.</p>
+<p>After executing the assembunny code in your puzzle input, <em>what value is left in register <code>a</code>?</em></p>
+</article>
+<p>Your puzzle answer was <code>318009</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>As you head down the fire escape to the monorail, you notice it didn't start; register <code>c</code> needs to be initialized to the position of the ignition key.</p>
+<p>If you instead <em>initialize register <code>c</code> to be <code>1</code></em>, what value is now left in register <code>a</code>?</p>
+</article>
+<p>Your puzzle answer was <code>9227663</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="12/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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+></span>]</span> this puzzle.</p>
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