advent-of-code-03.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.  You do risk spoiling a few
  19 surprises for yourself, though.  Best to play the normal way and discover
  20 everything as it was intended, I think.  The best surprises don't even appear
  21 in the source until you unlock them for real.
  22
  23 Please be careful with automated requests; I'm not Google, and I can only take
  24 so much traffic.  Please be considerate so that everyone gets to play.
  25
  26 If you're curious about how Advent of Code works, it's running on some custom
  27 Perl code. Other than a few integrations (auth, analytics, ads, social media),
  28 I built the whole thing myself, including the design, animations, prose, and
  29 all of the puzzles.
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  31 The puzzles probably took the longest; the easiest ones were around 45 minutes
  32 each, but the harder ones took 2-3 hours, some even longer than that. A lot of
  33 effort went into building this thing - I hope you're enjoying playing it as
  34 much as I enjoyed making it for you!
  35
  36 If you'd like to hang out, I'm @ericwastl on Twitter.
  37
  38 - Eric Wastl
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  90 <body>
  91 <header><h1><a href="/">Advent of Code</a></h1><div class="user">Neil Smith <span class="star-count">26*</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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 106 <article class="day-desc"><h2>--- Day 3: Perfectly Spherical Houses in a Vacuum ---</h2><p>Santa is delivering presents to an infinite two-dimensional grid of houses.</p>
 107 <p>He begins by delivering a present to the house at his starting location, and then an elf at the North Pole calls him via radio and tells him where to move next.  Moves are always exactly one house to the north (<code>^</code>), south (<code>v</code>), east (<code>&gt;</code>), or west (<code>&lt;</code>).  After each move, he delivers another present to the house at his new location.</p>
 108 <p>However, the elf back at the north pole has had a little too much eggnog, and so his directions are a little off, and Santa ends up visiting some houses more than once.  How many houses receive <em>at least one present</em>?</p>
 109 <p>For example:</p>
 110 <ul>
 111 <li><code>&gt;</code> delivers presents to <code>2</code> houses: one at the starting location, and one to the east.</li>
 112 <li><code>^&gt;v&lt;</code> delivers presents to <code>4</code> houses in a square, including twice to the house at his starting/ending location.</li>
 113 <li><code>^v^v^v^v^v</code> delivers a bunch of presents to some very lucky children at only <code>2</code> houses.</li>
 114 </ul>
 115 </article>
 116 <p>Your puzzle answer was <code>2081</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>The next year, to speed up the process, Santa creates a robot version of himself, <em>Robo-Santa</em>, to deliver presents with him.</p>
 117 <p>Santa and Robo-Santa start at the same location (delivering two presents to the same starting house), then take turns moving based on instructions from the elf, who is <span title="This absolutely real word was invented by someone flipping eggnoggedly through a dictionary.">eggnoggedly</span> reading from the same script as the previous year.</p>
 118 <p>This year, how many houses receive <em>at least one present</em>?</p>
 119 <p>For example:</p>
 120 <ul>
 121 <li><code>^v</code> delivers presents to <code>3</code> houses, because Santa goes north, and then Robo-Santa goes south.</li>
 122 <li><code>^&gt;v&lt;</code> now delivers presents to <code>3</code> houses, and Santa and Robo-Santa end up back where they started.</li>
 123 <li><code>^v^v^v^v^v</code> now delivers presents to <code>11</code> houses, with Santa going one direction and Robo-Santa going the other.</li>
 124 </ul>
 125 </article>
 126 <p>Your puzzle answer was <code>2341</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
 127 <p>At this point, you should <a href="/">return to your advent calendar</a> and try another puzzle.</p>
 128 <p>If you still want to see it, you can <a href="/day/3/input" target="_blank">get your puzzle input</a>.</p>
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 134  this puzzle.</p>
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