problems/day23.html

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  16 Oh, hello!  Funny seeing you here.
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  18 I appreciate your enthusiasm, but you aren't going to find much down here.
  19 There certainly aren't clues to any of the puzzles.  The best surprises don't
  20 even appear in the source until you unlock them for real.
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  22 Please be careful with automated requests; I'm not Google, and I can only take
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  25 If you're curious about how Advent of Code works, it's running on some custom
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  30 The puzzles are most of the work; the easiest ones take 3-4 hours each, but the
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  35 If you'd like to hang out, I'm @ericwastl on Twitter.
  36
  37 - Eric Wastl
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  90 <header><div><h1 class="title-global"><a href="/">Advent of Code</a></h1><nav><ul><li><a href="/2018/about">[About]</a></li><li><a href="/2018/events">[Events]</a></li><li><a href="https://teespring.com/adventofcode-2019" target="_blank">[Shop]</a></li><li><a href="/2018/settings">[Settings]</a></li><li><a href="/2018/auth/logout">[Log Out]</a></li></ul></nav><div class="user">Neil Smith <a href="/2018/support" class="supporter-badge" title="Advent of Code Supporter">(AoC++)</a> <span class="star-count">46*</span></div></div><div><h1 class="title-event">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="title-event-wrap">/^</span><a href="/2018">2018</a><span class="title-event-wrap">$/</span></h1><nav><ul><li><a href="/2018">[Calendar]</a></li><li><a href="/2018/support">[AoC++]</a></li><li><a href="/2018/sponsors">[Sponsors]</a></li><li><a href="/2018/leaderboard">[Leaderboard]</a></li><li><a href="/2018/stats">[Stats]</a></li></ul></nav></div></header>
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  97 <article class="day-desc"><h2>--- Day 23: Experimental Emergency Teleportation ---</h2><p>Using your torch to search the darkness of the rocky cavern, you finally locate the man's friend: a small <em>reindeer</em>.</p>
  98 <p>You're not sure how it got so far in this cave.  It looks sick - too sick to walk - and too heavy for you to carry all the way back.  Sleighs won't be invented for another 1500 years, of course.</p>
  99 <p>The only option is <em>experimental emergency teleportation</em>.</p>
 100 <p>You hit the "experimental emergency teleportation" <span title="We've always had this button; we've just been too scared to press it.">button</span> on the device and push <em>I accept the risk</em> on no fewer than 18 different warning messages. Immediately, the device deploys hundreds of tiny <em>nanobots</em> which fly around the cavern, apparently assembling themselves into a very specific <em>formation</em>. The device lists the <code>X,Y,Z</code> position (<code>pos</code>) for each nanobot as well as its <em>signal radius</em> (<code>r</code>) on its tiny screen (your puzzle input).</p>
 101 <p>Each nanobot can transmit signals to any integer coordinate which is a distance away from it <em>less than or equal to</em> its signal radius (as measured by <a href="https://en.wikipedia.org/wiki/Taxicab_geometry">Manhattan distance</a>). Coordinates a distance away of less than or equal to a nanobot's signal radius are said to be <em>in range</em> of that nanobot.</p>
 102 <p>Before you start the teleportation process, you should determine which nanobot is the <em>strongest</em> (that is, which has the largest signal radius) and then, for that nanobot, the <em>total number of nanobots that are in range</em> of it, <em>including itself</em>.</p>
 103 <p>For example, given the following nanobots:</p>
 104 <pre><code>pos=&lt;0,0,0&gt;, r=4
 105 pos=&lt;1,0,0&gt;, r=1
 106 pos=&lt;4,0,0&gt;, r=3
 107 pos=&lt;0,2,0&gt;, r=1
 108 pos=&lt;0,5,0&gt;, r=3
 109 pos=&lt;0,0,3&gt;, r=1
 110 pos=&lt;1,1,1&gt;, r=1
 111 pos=&lt;1,1,2&gt;, r=1
 112 pos=&lt;1,3,1&gt;, r=1
 113 </code></pre>
 114 <p>The strongest nanobot is the first one (position <code>0,0,0</code>) because its signal radius, <code>4</code> is the largest. Using that nanobot's location and signal radius, the following nanobots are in or out of range:</p>
 115 <ul>
 116 <li>The nanobot at <code>0,0,0</code> is distance <code>0</code> away, and so it is <em>in range</em>.</li>
 117 <li>The nanobot at <code>1,0,0</code> is distance <code>1</code> away, and so it is <em>in range</em>.</li>
 118 <li>The nanobot at <code>4,0,0</code> is distance <code>4</code> away, and so it is <em>in range</em>.</li>
 119 <li>The nanobot at <code>0,2,0</code> is distance <code>2</code> away, and so it is <em>in range</em>.</li>
 120 <li>The nanobot at <code>0,5,0</code> is distance <code>5</code> away, and so it is <em>not</em> in range.</li>
 121 <li>The nanobot at <code>0,0,3</code> is distance <code>3</code> away, and so it is <em>in range</em>.</li>
 122 <li>The nanobot at <code>1,1,1</code> is distance <code>3</code> away, and so it is <em>in range</em>.</li>
 123 <li>The nanobot at <code>1,1,2</code> is distance <code>4</code> away, and so it is <em>in range</em>.</li>
 124 <li>The nanobot at <code>1,3,1</code> is distance <code>5</code> away, and so it is <em>not</em> in range.</li>
 125 </ul>
 126 <p>In this example, in total, <code><em>7</em></code> nanobots are in range of the nanobot with the largest signal radius.</p>
 127 <p>Find the nanobot with the largest signal radius.  <em>How many nanobots are in range</em> of its signals?</p>
 128 </article>
 129 <p>Your puzzle answer was <code>510</code>.</p><article class="day-desc"><h2 id="part2">--- Part Two ---</h2><p>Now, you just need to figure out where to position yourself so that you're actually teleported when the nanobots activate.</p>
 130 <p>To increase the probability of success, you need to find the coordinate which puts you <em>in range of the largest number of nanobots</em>. If there are multiple, choose one <em>closest to your position</em> (<code>0,0,0</code>, measured by manhattan distance).</p>
 131 <p>For example, given the following nanobot formation:</p>
 132 <pre><code>pos=&lt;10,12,12&gt;, r=2
 133 pos=&lt;12,14,12&gt;, r=2
 134 pos=&lt;16,12,12&gt;, r=4
 135 pos=&lt;14,14,14&gt;, r=6
 136 pos=&lt;50,50,50&gt;, r=200
 137 pos=&lt;10,10,10&gt;, r=5
 138 </code></pre>
 139 <p>Many coordinates are in range of some of the nanobots in this formation.  However, only the coordinate <code>12,12,12</code> is in range of the most nanobots: it is in range of the first five, but is not in range of the nanobot at <code>10,10,10</code>. (All other coordinates are in range of fewer than five nanobots.) This coordinate's distance from <code>0,0,0</code> is <code><em>36</em></code>.</p>
 140 <p>Find the coordinates that are in range of the largest number of nanobots. <em>What is the shortest manhattan distance between any of those points and <code>0,0,0</code>?</em></p>
 141 </article>
 142 <p>Your puzzle answer was <code>108889300</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
 143 <p>At this point, you should <a href="/2018">return to your Advent calendar</a> and try another puzzle.</p>
 144 <p>If you still want to see it, you can <a href="23/input" target="_blank">get your puzzle input</a>.</p>
 145 <p>You can also <span class="share">[Share<span class="share-content">on
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