--- /dev/null
+<!DOCTYPE html>
+<html lang="en-us">
+<head>
+<meta charset="utf-8"/>
+<title>Day 1 - Advent of Code 2017</title>
+<!--[if lt IE 9]><script src="/static/html5.js"></script><![endif]-->
+<link href='//fonts.googleapis.com/css?family=Source+Code+Pro:300&subset=latin,latin-ext' rel='stylesheet' type='text/css'>
+<link rel="stylesheet" type="text/css" href="/static/style.css?11"/>
+<link rel="shortcut icon" href="/favicon.ico?2"/>
+</head><!--
+
+
+
+
+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 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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+-->
+<body>
+<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">4*</span></div></div><div><h1 class="title-event"> <span class="title-event-wrap">λy.</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>
+
+<div id="sidebar">
+<div id="sponsor"><div class="quiet">Our <a href="/2017/sponsors">sponsors</a> help make Advent of Code possible:</div><p><a href="https://cheppers.com/" target="_blank" onclick="if(ga)ga('send','event','sponsor','click',this.href);" rel="noopener">Cheppers</a> - xor(Pz0pQUI7Ch cmER8YDAEYAh4L GwEP, ↑↑↓↓←→←→BA)</p></div>
+<div id="ad">
+<script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
+<!-- Advent of Code Wide Skyscraper -->
+<ins class="adsbygoogle"
+ style="display:inline-block;width:160px;height:600px"
+ data-ad-client="ca-pub-9420604735624631"
+ data-ad-slot="8014013294"></ins>
+<script>
+(adsbygoogle = window.adsbygoogle || []).push({});
+</script>
+</div><!--/ad-->
+</div><!--/sidebar-->
+
+<main>
+<article class="day-desc"><h2>--- Day 1: Inverse Captcha ---</h2><p>The night before Christmas, one of Santa's Elves calls you in a panic. "The printer's broken! We can't print the <em>Naughty or Nice List</em>!" By the time you make it to <span title="Floor 17: cafeteria, printing department, and experimental organic digitization equipment.">sub-basement 17</span>, there are only a few minutes until midnight. "We have a big problem," she says; "there must be almost <em>fifty</em> bugs in this system, but nothing else can print The List. Stand in this square, quick! There's no time to explain; if you can convince them to pay you in <em class="star">stars</em>, you'll be able to--" She pulls a lever and the world goes blurry.</p>
+<p>When your eyes can focus again, everything seems a lot more pixelated than before. She must have sent you inside the computer! You check the system clock: <em>25 milliseconds</em> until midnight. With that much time, you should be able to collect all <em class="star">fifty stars</em> by December 25th.</p>
+<p>Collect stars by solving puzzles. Two puzzles will be made available on each <s style="text-decoration-color:#fff;">day</s> millisecond in the advent calendar; the second puzzle is unlocked when you complete the first. Each puzzle grants <em class="star">one star</em>. Good luck!</p>
+<p>You're standing in a room with "digitization quarantine" written in LEDs along one wall. The only door is locked, but it includes a small interface. "Restricted Area - Strictly No Digitized Users Allowed."</p>
+<p>It goes on to explain that you may only leave by solving a <a href="https://en.wikipedia.org/wiki/CAPTCHA">captcha</a> to prove you're <em>not</em> a human. Apparently, you only get one millisecond to solve the captcha: too fast for a normal human, but it feels like hours to you.</p>
+<p>The captcha requires you to review a sequence of digits (your puzzle input) and find the <em>sum</em> of all digits that match the <em>next</em> digit in the list. The list is circular, so the digit after the last digit is the <em>first</em> digit in the list.</p>
+<p>For example:</p>
+<ul>
+<li><code>1122</code> produces a sum of <code>3</code> (<code>1</code> + <code>2</code>) because the first digit (<code>1</code>) matches the second digit and the third digit (<code>2</code>) matches the fourth digit.</li>
+<li><code>1111</code> produces <code>4</code> because each digit (all <code>1</code>) matches the next.</li>
+<li><code>1234</code> produces <code>0</code> because no digit matches the next.</li>
+<li><code>91212129</code> produces <code>9</code> because the only digit that matches the next one is the last digit, <code>9</code>.</li>
+</ul>
+<p><em>What is the solution</em> to your captcha?</p>
+</article>
+<p>Your puzzle answer was <code>1158</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>You notice a progress bar that jumps to 50% completion. Apparently, the door isn't yet satisfied, but it did emit a <em class="star">star</em> as encouragement. The instructions change:</p>
+<p>Now, instead of considering the <em>next</em> digit, it wants you to consider the digit <em>halfway around</em> the circular list. That is, if your list contains <code>10</code> items, only include a digit in your sum if the digit <code>10/2 = 5</code> steps forward matches it. Fortunately, your list has an even number of elements.</p>
+<p>For example:</p>
+<ul>
+<li><code>1212</code> produces <code>6</code>: the list contains <code>4</code> items, and all four digits match the digit <code>2</code> items ahead.</li>
+<li><code>1221</code> produces <code>0</code>, because every comparison is between a <code>1</code> and a <code>2</code>.</li>
+<li><code>123425</code> produces <code>4</code>, because both <code>2</code>s match each other, but no other digit has a match.</li>
+<li><code>123123</code> produces <code>12</code>.</li>
+<li><code>12131415</code> produces <code>4</code>.</li>
+</ul>
+<p><em>What is the solution</em> to your new captcha?</p>
+</article>
+<p>Your puzzle answer was <code>1132</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="1/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+%22Inverse+Captcha%22+%2D+Day+1+%2D+Advent+of+Code+2017&url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F1&related=ericwastl&hashtags=AdventOfCode" target="_blank">Twitter</a>
+ <a href="https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F1" target="_blank">Google+</a>
+ <a href="http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F1&title=I%27ve+completed+%22Inverse+Captcha%22+%2D+Day+1+%2D+Advent+of+Code+2017" target="_blank">Reddit</a
+></span>]</span> this puzzle.</p>
+</main>
+
+<!-- ga -->
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--- /dev/null
+<!DOCTYPE html>
+<html lang="en-us">
+<head>
+<meta charset="utf-8"/>
+<title>Day 2 - Advent of Code 2017</title>
+<!--[if lt IE 9]><script src="/static/html5.js"></script><![endif]-->
+<link href='//fonts.googleapis.com/css?family=Source+Code+Pro:300&subset=latin,latin-ext' rel='stylesheet' type='text/css'>
+<link rel="stylesheet" type="text/css" href="/static/style.css?11"/>
+<link rel="shortcut icon" href="/favicon.ico?2"/>
+</head><!--
+
+
+
+
+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 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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+
+
+
+
+
+-->
+<body>
+<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">4*</span></div></div><div><h1 class="title-event"> <span class="title-event-wrap">/^</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>
+
+<div id="sidebar">
+<div id="sponsor"><div class="quiet">Our <a href="/2017/sponsors">sponsors</a> help make Advent of Code possible:</div><p><a href="http://smartystreets.com/aoc" target="_blank" onclick="if(ga)ga('send','event','sponsor','click',this.href);" rel="noopener">SmartyStreets</a> - U2VuZGluZyBDaH Jpc3RtYXMgY2Fy ZHMgdG8gYmFkIG FkZHJlc3Nlcz8K</p></div>
+<div id="ad">
+<script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
+<!-- Advent of Code Wide Skyscraper -->
+<ins class="adsbygoogle"
+ style="display:inline-block;width:160px;height:600px"
+ data-ad-client="ca-pub-9420604735624631"
+ data-ad-slot="8014013294"></ins>
+<script>
+(adsbygoogle = window.adsbygoogle || []).push({});
+</script>
+</div><!--/ad-->
+</div><!--/sidebar-->
+
+<main>
+<article class="day-desc"><h2>--- Day 2: Corruption Checksum ---</h2><p>As you walk through the door, a glowing humanoid shape yells in your direction. "You there! Your state appears to be idle. Come help us repair the corruption in this spreadsheet - if we take another millisecond, we'll have to display an hourglass cursor!"</p>
+<p>The spreadsheet consists of rows of apparently-random numbers. To make sure the recovery process is on the right track, they need you to calculate the spreadsheet's <em>checksum</em>. For each row, determine the difference between the largest value and the smallest value; the checksum is the sum of all of these differences.</p>
+<p>For example, given the following spreadsheet:</p>
+<pre><code>5 1 9 5
+7 5 3
+2 4 6 8</code></pre>
+<ul>
+<li>The first row's largest and smallest values are <code>9</code> and <code>1</code>, and their difference is <code>8</code>.</li>
+<li>The second row's largest and smallest values are <code>7</code> and <code>3</code>, and their difference is <code>4</code>.</li>
+<li>The third row's difference is <code>6</code>.</li>
+</ul>
+<p>In this example, the spreadsheet's checksum would be <code>8 + 4 + 6 = 18</code>.</p>
+<p><em>What is the checksum</em> for the spreadsheet in your puzzle input?</p>
+</article>
+<p>Your puzzle answer was <code>39126</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>"Great work; looks like we're on the right track after all. Here's a <em class="star">star</em> for your effort." However, the program seems a little worried. Can programs <em>be</em> worried?</p>
+<p>"Based on what we're seeing, it looks like all the User wanted is some information about the <em>evenly divisible values</em> in the spreadsheet. Unfortunately, none of us are equipped for that kind of calculation - most of us specialize in <span title="Bonus points if you solve this part using only bitwise operations.">bitwise operations</span>."</p>
+<p>It sounds like the goal is to find the only two numbers in each row where one evenly divides the other - that is, where the result of the division operation is a whole number. They would like you to find those numbers on each line, divide them, and add up each line's result.</p>
+<p>For example, given the following spreadsheet:</p>
+<pre><code>5 9 2 8
+9 4 7 3
+3 8 6 5</code></pre>
+<ul>
+<li>In the first row, the only two numbers that evenly divide are <code>8</code> and <code>2</code>; the result of this division is <code>4</code>.</li>
+<li>In the second row, the two numbers are <code>9</code> and <code>3</code>; the result is <code>3</code>.</li>
+<li>In the third row, the result is <code>2</code>.</li>
+</ul>
+<p>In this example, the sum of the results would be <code>4 + 3 + 2 = 9</code>.</p>
+<p>What is the <em>sum of each row's result</em> in your puzzle input?</p>
+</article>
+<p>Your puzzle answer was <code>258</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="2/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+%22Corruption+Checksum%22+%2D+Day+2+%2D+Advent+of+Code+2017&url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F2&related=ericwastl&hashtags=AdventOfCode" target="_blank">Twitter</a>
+ <a href="https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F2" target="_blank">Google+</a>
+ <a href="http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F2&title=I%27ve+completed+%22Corruption+Checksum%22+%2D+Day+2+%2D+Advent+of+Code+2017" target="_blank">Reddit</a
+></span>]</span> this puzzle.</p>
+</main>
+
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