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+<title>Day 23 - Advent of Code</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. You do risk spoiling a few
+surprises for yourself, though. Best to play the normal way and discover
+everything as it was intended, I think. 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, some 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><h1><a href="/">Advent of Code</a></h1><div class="user">Neil Smith <span class="star-count">46*</span></div><nav><ul><li><a href="/about">[About]</a></li><li><a href="/stats">[Stats]</a></li><li><a href="/leaderboard">[Leaderboard]</a></li><li><a href="/settings">[Settings]</a></li><li><a href="/auth/logout">[Log out]</a></li></ul></nav></header>
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+
+<main>
+<article class="day-desc"><h2>--- Day 23: Opening the Turing Lock ---</h2><p>Little Jane Marie just got her very first computer for Christmas from some <span title="Definitely not Wintermute.">unknown benefactor</span>. It comes with instructions and an example program, but the computer itself seems to be malfunctioning. She's curious what the program does, and would like you to help her run it.</p>
+<p>The manual explains that the computer supports two <a href="https://en.wikipedia.org/wiki/Processor_register">registers</a> and six <a href="https://en.wikipedia.org/wiki/Instruction_set">instructions</a> (truly, it goes on to remind the reader, a state-of-the-art technology). The registers are named <code>a</code> and <code>b</code>, can hold any <a href="https://en.wikipedia.org/wiki/Natural_number">non-negative integer</a>, and begin with a value of <code>0</code>. The instructions are as follows:</p>
+<ul>
+<li><code>hlf r</code> sets register <code>r</code> to <em>half</em> its current value, then continues with the next instruction.</li>
+<li><code>tpl r</code> sets register <code>r</code> to <em>triple</em> its current value, then continues with the next instruction.</li>
+<li><code>inc r</code> <em>increments</em> register <code>r</code>, adding <code>1</code> to it, then continues with the next instruction.</li>
+<li><code>jmp offset</code> is a <em>jump</em>; it continues with the instruction <code>offset</code> away <em>relative to itself</em>.</li>
+<li><code>jie r, offset</code> is like <code>jmp</code>, but only jumps if register <code>r</code> is <em>even</em> ("jump if even").</li>
+<li><code>jio r, offset</code> is like <code>jmp</code>, but only jumps if register <code>r</code> is <code>1</code> ("jump if <em>one</em>", not odd).</li>
+</ul>
+<p>All three jump instructions work with an <em>offset</em> relative to that instruction. The offset is always written with a prefix <code>+</code> or <code>-</code> to indicate the direction of the jump (forward or backward, respectively). For example, <code>jmp +1</code> would simply continue with the next instruction, while <code>jmp +0</code> would continuously jump back to itself forever.</p>
+<p>The program exits when it tries to run an instruction beyond the ones defined.</p>
+<p>For example, this program sets <code>a</code> to <code>2</code>, because the <code>jio</code> instruction causes it to skip the <code>tpl</code> instruction:</p>
+<pre><code>inc a
+jio a, +2
+tpl a
+inc a
+</code></pre>
+<p>What is <em>the value in register <code>b</code></em> when the program in your puzzle input is finished executing?</p>
+</article>
+<p>Your puzzle answer was <code>307</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>The unknown benefactor is <em>very</em> thankful for releasi-- er, helping little Jane Marie with her computer. Definitely not to distract you, what is the value in register <code>b</code> after the program is finished executing if register <code>a</code> starts as <code>1</code> instead?</p>
+</article>
+<p>Your puzzle answer was <code>160</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="/">return to your advent calendar</a> and try another puzzle.</p>
+<p>If you still want to see it, you can <a href="/day/23/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+%22Opening+the+Turing+Lock%22+%2D+Day+23+%2D+Advent+of+Code&url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F23&related=ericwastl&hashtags=AdventOfCode" target="_blank">Twitter</a>
+ <a href="https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F23" target="_blank">Google+</a>
+ <a href="http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F23&title=I%27ve+completed+%22Opening+the+Turing+Lock%22+%2D+Day+23+%2D+Advent+of+Code" target="_blank">Reddit</a
+></span>]</span>
+ this puzzle.</p>
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