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1 - Advent of Code
2016</title>
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15 Oh, hello! Funny seeing you here.
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.
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.
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
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!
34 If you'd like to hang out, I'm @ericwastl on Twitter.
89 <header><div><h1 class=
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107 <article class=
"day-desc"><h2>--- Day
1: No Time for a Taxicab ---
</h2><p>Santa's sleigh uses a
<span title=
"An atomic clock is too inaccurate; he might end up in a wall!">very high-precision clock
</span> to guide its movements, and the clock's oscillator is regulated by stars. Unfortunately, the stars have been stolen... by the Easter Bunny. To save Christmas, Santa needs you to retrieve all
<em class=
"star">fifty stars
</em> by December
25th.
</p>
108 <p>Collect stars by solving puzzles. Two puzzles will be made available on each day 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>
109 <p>You're airdropped near
<em>Easter Bunny Headquarters
</em> in a city somewhere.
"Near", unfortunately, is as close as you can get - the instructions on the Easter Bunny Recruiting Document the Elves intercepted start here, and nobody had time to work them out further.
</p>
110 <p>The Document indicates that you should start at the given coordinates (where you just landed) and face North. Then, follow the provided sequence: either turn left (
<code>L
</code>) or right (
<code>R
</code>)
90 degrees, then walk forward the given number of blocks, ending at a new intersection.
</p>
111 <p>There's no time to follow such ridiculous instructions on foot, though, so you take a moment and work out the destination. Given that you can only walk on the
<a href=
"https://en.wikipedia.org/wiki/Taxicab_geometry">street grid of the city
</a>, how far is the shortest path to the destination?
</p>
114 <li>Following
<code>R2, L3
</code> leaves you
<code>2</code> blocks East and
<code>3</code> blocks North, or
<code>5</code> blocks away.
</li>
115 <li><code>R2, R2, R2
</code> leaves you
<code>2</code> blocks due South of your starting position, which is
<code>2</code> blocks away.
</li>
116 <li><code>R5, L5, R5, R3
</code> leaves you
<code>12</code> blocks away.
</li>
118 <p><em>How many blocks away
</em> is Easter Bunny HQ?
</p>
120 <p>Your puzzle answer was
<code>246</code>.
</p><article class=
"day-desc"><h2>--- Part Two ---
</h2><p>Then, you notice the instructions continue on the back of the Recruiting Document. Easter Bunny HQ is actually at the first location you visit twice.
</p>
121 <p>For example, if your instructions are
<code>R8, R4, R4, R8
</code>, the first location you visit twice is
<code>4</code> blocks away, due East.
</p>
122 <p>How many blocks away is the
<em>first location you visit twice
</em>?
</p>
124 <p>Your puzzle answer was
<code>124</code>.
</p><p class=
"day-success">Both parts of this puzzle are complete! They provide two gold stars: **
</p>
125 <p>At this point, you should
<a href=
"/2016">return to your advent calendar
</a> and try another puzzle.
</p>
126 <p>If you still want to see it, you can
<a href=
"1/input" target=
"_blank">get your puzzle input
</a>.
</p>
127 <p>You can also
<span class=
"share">[Share
<span class=
"share-content">on
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131 ></span>]
</span> this puzzle.
</p>
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