problems/day02.html

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  15 Oh, hello!  Funny seeing you here.
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  17 I appreciate your enthusiasm, but you aren't going to find much down here.
  18 There certainly aren't clues to any of the puzzles.  The best surprises don't
  19 even appear in the source until you unlock them for real.
  20
  21 Please be careful with automated requests; I'm not Google, and I can only take
  22 so much traffic.  Please be considerate so that everyone gets to play.
  23
  24 If you're curious about how Advent of Code works, it's running on some custom
  25 Perl code. Other than a few integrations (auth, analytics, ads, social media),
  26 I built the whole thing myself, including the design, animations, prose, and
  27 all of the puzzles.
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  29 The puzzles probably took the longest; the easiest ones took an hour or two
  30 each, but the harder ones took 4-5 hours, and a few even longer than that. A
  31 lot of effort went into building this thing - I hope you're enjoying playing it
  32 as much as I enjoyed making it for you!
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  34 If you'd like to hang out, I'm @ericwastl on Twitter.
  35
  36 - Eric Wastl
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  88 <body>
  89 <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">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<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>
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 107 <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>
 108 <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>
 109 <p>For example, given the following spreadsheet:</p>
 110 <pre><code>5 1 9 5
 111 7 5 3
 112 2 4 6 8</code></pre>
 113 <ul>
 114 <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>
 115 <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>
 116 <li>The third row's difference is <code>6</code>.</li>
 117 </ul>
 118 <p>In this example, the spreadsheet's checksum would be <code>8 + 4 + 6 = 18</code>.</p>
 119 <p><em>What is the checksum</em> for the spreadsheet in your puzzle input?</p>
 120 </article>
 121 <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>
 122 <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>
 123 <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>
 124 <p>For example, given the following spreadsheet:</p>
 125 <pre><code>5 9 2 8
 126 9 4 7 3
 127 3 8 6 5</code></pre>
 128 <ul>
 129 <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>
 130 <li>In the second row, the two numbers are <code>9</code> and <code>3</code>; the result is <code>3</code>.</li>
 131 <li>In the third row, the result is <code>2</code>.</li>
 132 </ul>
 133 <p>In this example, the sum of the results would be <code>4 + 3 + 2 = 9</code>.</p>
 134 <p>What is the <em>sum of each row's result</em> in your puzzle input?</p>
 135 </article>
 136 <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>
 137 <p>At this point, you should <a href="/2017">return to your advent calendar</a> and try another puzzle.</p>
 138 <p>If you still want to see it, you can <a href="2/input" target="_blank">get your puzzle input</a>.</p>
 139 <p>You can also <span class="share">[Share<span class="share-content">on
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