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+<title>Day 3 - Advent of Code 2020</title>
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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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+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
+of the puzzles.
+
+The puzzles are most of the work; preparing a new calendar and a new set of
+puzzles each year takes all of my free time for 4-5 months. A lot of effort
+went into building this thing - I hope you're enjoying playing it as much as I
+enjoyed making it for you!
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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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+<body>
+<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">6*</span></div></div><div><h1 class="title-event">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="title-event-wrap">y(</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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+<script>window.addEventListener('click', function(e,s,r){if(e.target.nodeName==='CODE'&&e.detail===3){s=window.getSelection();s.removeAllRanges();r=document.createRange();r.selectNodeContents(e.target);s.addRange(r);}});</script>
+<article class="day-desc"><h2>--- Day 3: Toboggan Trajectory ---</h2><p>With the toboggan login problems resolved, you set off toward the airport. While travel by toboggan might be easy, it's certainly not safe: there's <span title="It looks like the toboggan steering system even runs on Intcode! Good thing you don't have to modify it.">very minimal steering</span> and the area is covered in trees. You'll need to see which angles will take you near the fewest trees.</p>
+<p>Due to the local geology, trees in this area only grow on exact integer coordinates in a grid. You make a map (your puzzle input) of the open squares (<code>.</code>) and trees (<code>#</code>) you can see. For example:</p>
+<pre><code>..##.......
+#...#...#..
+.#....#..#.
+..#.#...#.#
+.#...##..#.
+..#.##.....
+.#.#.#....#
+.#........#
+#.##...#...
+#...##....#
+.#..#...#.#
+</code></pre>
+<p>These aren't the only trees, though; due to something you read about once involving arboreal genetics and biome stability, the same pattern repeats to the right many times:</p>
+<pre><code><em>..##.......</em>..##.........##.........##.........##.........##.......  ---&gt;
+<em>#...#...#..</em>#...#...#..#...#...#..#...#...#..#...#...#..#...#...#..
+<em>.#....#..#.</em>.#....#..#..#....#..#..#....#..#..#....#..#..#....#..#.
+<em>..#.#...#.#</em>..#.#...#.#..#.#...#.#..#.#...#.#..#.#...#.#..#.#...#.#
+<em>.#...##..#.</em>.#...##..#..#...##..#..#...##..#..#...##..#..#...##..#.
+<em>..#.##.....</em>..#.##.......#.##.......#.##.......#.##.......#.##.....  ---&gt;
+<em>.#.#.#....#</em>.#.#.#....#.#.#.#....#.#.#.#....#.#.#.#....#.#.#.#....#
+<em>.#........#</em>.#........#.#........#.#........#.#........#.#........#
+<em>#.##...#...</em>#.##...#...#.##...#...#.##...#...#.##...#...#.##...#...
+<em>#...##....#</em>#...##....##...##....##...##....##...##....##...##....#
+<em>.#..#...#.#</em>.#..#...#.#.#..#...#.#.#..#...#.#.#..#...#.#.#..#...#.#  ---&gt;
+</code></pre>
+<p>You start on the open square (<code>.</code>) in the top-left corner and need to reach the bottom (below the bottom-most row on your map).</p>
+<p>The toboggan can only follow a few specific slopes (you opted for a cheaper model that prefers rational numbers); start by <em>counting all the trees</em> you would encounter for the slope <em>right 3, down 1</em>:</p>
+<p>From your starting position at the top-left, check the position that is right 3 and down 1. Then, check the position that is right 3 and down 1 from there, and so on until you go past the bottom of the map.</p>
+<p>The locations you'd check in the above example are marked here with <code><em>O</em></code> where there was an open square and <code><em>X</em></code> where there was a tree:</p>
+<pre><code>..##.........##.........##.........##.........##.........##.......  ---&gt;
+#..<em>O</em>#...#..#...#...#..#...#...#..#...#...#..#...#...#..#...#...#..
+.#....<em>X</em>..#..#....#..#..#....#..#..#....#..#..#....#..#..#....#..#.
+..#.#...#<em>O</em>#..#.#...#.#..#.#...#.#..#.#...#.#..#.#...#.#..#.#...#.#
+.#...##..#..<em>X</em>...##..#..#...##..#..#...##..#..#...##..#..#...##..#.
+..#.##.......#.<em>X</em>#.......#.##.......#.##.......#.##.......#.##.....  ---&gt;
+.#.#.#....#.#.#.#.<em>O</em>..#.#.#.#....#.#.#.#....#.#.#.#....#.#.#.#....#
+.#........#.#........<em>X</em>.#........#.#........#.#........#.#........#
+#.##...#...#.##...#...#.<em>X</em>#...#...#.##...#...#.##...#...#.##...#...
+#...##....##...##....##...#<em>X</em>....##...##....##...##....##...##....#
+.#..#...#.#.#..#...#.#.#..#...<em>X</em>.#.#..#...#.#.#..#...#.#.#..#...#.#  ---&gt;
+</code></pre>
+<p>In this example, traversing the map using this slope would cause you to encounter <code><em>7</em></code> trees.</p>
+<p>Starting at the top-left corner of your map and following a slope of right 3 and down 1, <em>how many trees would you encounter?</em></p>
+</article>
+<p>Your puzzle answer was <code>228</code>.</p><article class="day-desc"><h2 id="part2">--- Part Two ---</h2><p>Time to check the rest of the slopes - you need to minimize the probability of a sudden arboreal stop, after all.</p>
+<p>Determine the number of trees you would encounter if, for each of the following slopes, you start at the top-left corner and traverse the map all the way to the bottom:</p>
+<ul>
+<li>Right 1, down 1.</li>
+<li>Right 3, down 1. (This is the slope you already checked.)</li>
+<li>Right 5, down 1.</li>
+<li>Right 7, down 1.</li>
+<li>Right 1, down 2.</li>
+</ul>
+<p>In the above example, these slopes would find <code>2</code>, <code>7</code>, <code>3</code>, <code>4</code>, and <code>2</code> tree(s) respectively; multiplied together, these produce the answer <code><em>336</em></code>.</p>
+<p><em>What do you get if you multiply together the number of trees encountered on each of the listed slopes?</em></p>
+</article>
+<p>Your puzzle answer was <code>6818112000</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="3/input" target="_blank">get your puzzle input</a>.</p>
+<p>You can also <span class="share">[Share<span class="share-content">on
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+  <a href="javascript:void(0);" onclick="var mastodon_instance=prompt('Mastodon Instance / Server Name?'); if(typeof mastodon_instance==='string' && mastodon_instance.length){this.href='https://'+mastodon_instance+'/share?text=I%27ve+completed+%22Toboggan+Trajectory%22+%2D+Day+3+%2D+Advent+of+Code+2020+%23AdventOfCode+https%3A%2F%2Fadventofcode%2Ecom%2F2020%2Fday%2F3'}else{return false;}" target="_blank">Mastodon</a
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