day06.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 were around 45 minutes
  30 each, but the harder ones took 2-3 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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  89 <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">12*</span></div></div><div><h1 class="title-event">&nbsp;&nbsp;&nbsp;<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>
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 107 <article class="day-desc"><h2>--- Day 6: Signals and Noise ---</h2><p>Something is jamming your communications with Santa. Fortunately, your signal is only partially jammed, and protocol in situations like this is to switch to a simple <a href="https://en.wikipedia.org/wiki/Repetition_code">repetition code</a> to get the message through.</p>
 108 <p>In this model, the same message is sent repeatedly.  You've recorded the repeating message signal (your puzzle input), but the data seems quite corrupted - almost too badly to recover. <em>Almost</em>.</p>
 109 <p>All you need to do is figure out which character is most frequent for each position. For example, suppose you had recorded the following messages:</p>
 110 <pre><code>eedadn
 111 drvtee
 112 eandsr
 113 raavrd
 114 atevrs
 115 tsrnev
 116 sdttsa
 117 rasrtv
 118 nssdts
 119 ntnada
 120 svetve
 121 tesnvt
 122 vntsnd
 123 vrdear
 124 dvrsen
 125 enarar
 126 </code></pre>
 127 <p>The most common character in the first column is <code>e</code>; in the second, <code>a</code>; in the third, <code>s</code>, and so on. Combining these characters returns the error-corrected message, <code>easter</code>.</p>
 128 <p>Given the recording in your puzzle input, <em>what is the error-corrected version</em> of the message being sent?</p>
 129 </article>
 130 <p>Your puzzle answer was <code>umejzgdw</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>Of course, that <em>would</em> be the message - if you hadn't agreed to use a <em>modified repetition code</em> instead.</p>
 131 <p>In this <span title="*Please* don't try this at home.">modified code</span>, the sender instead transmits what looks like random data, but for each character, the character they actually want to send is <em>slightly less likely</em> than the others. Even after signal-jamming noise, you can look at the letter distributions in each column and choose the <em>least common</em> letter to reconstruct the original message.</p>
 132 <p>In the above example, the least common character in the first column is <code>a</code>; in the second, <code>d</code>, and so on. Repeating this process for the remaining characters produces the original message, <code>advent</code>.</p>
 133 <p>Given the recording in your puzzle input and this new decoding methodology, <em>what is the original message</em> that Santa is trying to send?</p>
 134 </article>
 135 <p>Your puzzle answer was <code>aovueakv</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
 136 <p>At this point, you should <a href="/2016">return to your advent calendar</a> and try another puzzle.</p>
 137 <p>If you still want to see it, you can <a href="6/input" target="_blank">get your puzzle input</a>.</p>
 138 <p>You can also <span class="share">[Share<span class="share-content">on
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 142 ></span>]</span> this puzzle.</p>
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