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+Oh, hello! Funny seeing you here.
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+I appreciate your enthusiasm, but you aren't going to find much down here.
+There certainly aren't clues to any of the puzzles. The best surprises don't
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+Please be careful with automated requests; I'm not a massive company, and I can
+only take so much traffic. Please be considerate so that everyone gets to play.
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+If you're curious about how Advent of Code works, it's running on some custom
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+built the whole thing myself, including the design, animations, prose, and all
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+The puzzles are most of the work; preparing a new calendar and a new set of
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+went into building this thing - I hope you're enjoying playing it as much as I
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+If you'd like to hang out, I'm @ericwastl on Twitter.
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+- Eric Wastl
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+<header><div><h1 class="title-global"><a href="/">Advent of Code</a></h1><nav><ul><li><a href="/2020/about">[About]</a></li><li><a href="/2020/events">[Events]</a></li><li><a href="https://teespring.com/stores/advent-of-code" target="_blank">[Shop]</a></li><li><a href="/2020/settings">[Settings]</a></li><li><a href="/2020/auth/logout">[Log Out]</a></li></ul></nav><div class="user">Neil Smith <a href="/2020/support" class="supporter-badge" title="Advent of Code Supporter">(AoC++)</a> <span class="star-count">32*</span></div></div><div><h1 class="title-event"> <span class="title-event-wrap">0x0000|</span><a href="/2020">2020</a><span class="title-event-wrap"></span></h1><nav><ul><li><a href="/2020">[Calendar]</a></li><li><a href="/2020/support">[AoC++]</a></li><li><a href="/2020/sponsors">[Sponsors]</a></li><li><a href="/2020/leaderboard">[Leaderboard]</a></li><li><a href="/2020/stats">[Stats]</a></li></ul></nav></div></header>
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+<article class="day-desc"><h2>--- Day 16: Ticket Translation ---</h2><p>As you're walking to yet another connecting flight, you realize that one of the legs of your re-routed trip coming up is on a high-speed train. However, the train ticket you were given is in a language you don't understand. You should probably figure out what it says before you get to the train station after the next flight.</p>
+<p>Unfortunately, you <span title="This actually happened to me once, but I solved it by just asking someone.">can't actually <em>read</em> the words on the ticket</span>. You can, however, read the numbers, and so you figure out <em>the fields these tickets must have</em> and <em>the valid ranges</em> for values in those fields.</p>
+<p>You collect the <em>rules for ticket fields</em>, the <em>numbers on your ticket</em>, and the <em>numbers on other nearby tickets</em> for the same train service (via the airport security cameras) together into a single document you can reference (your puzzle input).</p>
+<p>The <em>rules for ticket fields</em> specify a list of fields that exist <em>somewhere</em> on the ticket and the <em>valid ranges of values</em> for each field. For example, a rule like <code>class: 1-3 or 5-7</code> means that one of the fields in every ticket is named <code>class</code> and can be any value in the ranges <code>1-3</code> or <code>5-7</code> (inclusive, such that <code>3</code> and <code>5</code> are both valid in this field, but <code>4</code> is not).</p>
+<p>Each ticket is represented by a single line of comma-separated values. The values are the numbers on the ticket in the order they appear; every ticket has the same format. For example, consider this ticket:</p>
+<pre><code>.--------------------------------------------------------.
+| ????: 101 ?????: 102 ??????????: 103 ???: 104 |
+| |
+| ??: 301 ??: 302 ???????: 303 ??????? |
+| ??: 401 ??: 402 ???? ????: 403 ????????? |
+'--------------------------------------------------------'
+</code></pre>
+<p>Here, <code>?</code> represents text in a language you don't understand. This ticket might be represented as <code>101,102,103,104,301,302,303,401,402,403</code>; of course, the actual train tickets you're looking at are <em>much</em> more complicated. In any case, you've extracted just the numbers in such a way that the first number is always the same specific field, the second number is always a different specific field, and so on - you just don't know what each position actually means!</p>
+<p>Start by determining which tickets are <em>completely invalid</em>; these are tickets that contain values which <em>aren't valid for any field</em>. Ignore <em>your ticket</em> for now.</p>
+<p>For example, suppose you have the following notes:</p>
+<pre><code>class: 1-3 or 5-7
+row: 6-11 or 33-44
+seat: 13-40 or 45-50
+
+your ticket:
+7,1,14
+
+nearby tickets:
+7,3,47
+40,<em>4</em>,50
+<em>55</em>,2,20
+38,6,<em>12</em>
+</code></pre>
+<p>It doesn't matter which position corresponds to which field; you can identify invalid <em>nearby tickets</em> by considering only whether tickets contain <em>values that are not valid for any field</em>. In this example, the values on the first <em>nearby ticket</em> are all valid for at least one field. This is not true of the other three <em>nearby tickets</em>: the values <code>4</code>, <code>55</code>, and <code>12</code> are are not valid for any field. Adding together all of the invalid values produces your <em>ticket scanning error rate</em>: <code>4 + 55 + 12</code> = <em><code>71</code></em>.</p>
+<p>Consider the validity of the <em>nearby tickets</em> you scanned. <em>What is your ticket scanning error rate?</em></p>
+</article>
+<p>Your puzzle answer was <code>25984</code>.</p><article class="day-desc"><h2 id="part2">--- Part Two ---</h2><p>Now that you've identified which tickets contain invalid values, <em>discard those tickets entirely</em>. Use the remaining valid tickets to determine which field is which.</p>
+<p>Using the valid ranges for each field, determine what order the fields appear on the tickets. The order is consistent between all tickets: if <code>seat</code> is the third field, it is the third field on every ticket, including <em>your ticket</em>.</p>
+<p>For example, suppose you have the following notes:</p>
+<pre><code>class: 0-1 or 4-19
+row: 0-5 or 8-19
+seat: 0-13 or 16-19
+
+your ticket:
+11,12,13
+
+nearby tickets:
+3,9,18
+15,1,5
+5,14,9
+</code></pre>
+<p>Based on the <em>nearby tickets</em> in the above example, the first position must be <code>row</code>, the second position must be <code>class</code>, and the third position must be <code>seat</code>; you can conclude that in <em>your ticket</em>, <code>class</code> is <code>12</code>, <code>row</code> is <code>11</code>, and <code>seat</code> is <code>13</code>.</p>
+<p>Once you work out which field is which, look for the six fields on <em>your ticket</em> that start with the word <code>departure</code>. <em>What do you get if you multiply those six values together?</em></p>
+</article>
+<p>Your puzzle answer was <code>1265347500049</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
+<p>At this point, you should <a href="/2020">return to your Advent calendar</a> and try another puzzle.</p>
+<p>If you still want to see it, you can <a href="16/input" target="_blank">get your puzzle input</a>.</p>
+<p>You can also <span class="share">[Share<span class="share-content">on
+ <a href="https://twitter.com/intent/tweet?text=I%27ve+completed+%22Ticket+Translation%22+%2D+Day+16+%2D+Advent+of+Code+2020&url=https%3A%2F%2Fadventofcode%2Ecom%2F2020%2Fday%2F16&related=ericwastl&hashtags=AdventOfCode" target="_blank">Twitter</a>
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+></span>]</span> this puzzle.</p>
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