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  17 Oh, hello!  Funny seeing you here.
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  19 I appreciate your enthusiasm, but you aren't going to find much down here.
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  31 The puzzles are most of the work; preparing a new calendar and a new set of
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  91 <header><div><h1 class="title-global"><a href="/">Advent of Code</a></h1><nav><ul><li><a href="/2022/about">[About]</a></li><li><a href="/2022/events">[Events]</a></li><li><a href="https://teespring.com/stores/advent-of-code" target="_blank">[Shop]</a></li><li><a href="/2022/settings">[Settings]</a></li><li><a href="/2022/auth/logout">[Log Out]</a></li></ul></nav><div class="user">Neil Smith <a href="/2022/support" class="supporter-badge" title="Advent of Code Supporter">(AoC++)</a> <span class="star-count">10*</span></div></div><div><h1 class="title-event">&nbsp;&nbsp;<span class="title-event-wrap">0.0.0.0:</span><a href="/2022">2022</a><span class="title-event-wrap"></span></h1><nav><ul><li><a href="/2022">[Calendar]</a></li><li><a href="/2022/support">[AoC++]</a></li><li><a href="/2022/sponsors">[Sponsors]</a></li><li><a href="/2022/leaderboard">[Leaderboard]</a></li><li><a href="/2022/stats">[Stats]</a></li></ul></nav></div></header>
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  98 <article class="day-desc"><h2>--- Day 5: Supply Stacks ---</h2><p>The expedition can depart as soon as the final supplies have been unloaded from the ships. Supplies are stored in stacks of marked <em>crates</em>, but because the needed supplies are buried under many other crates, the crates need to be rearranged.</p>
  99 <p>The ship has a <em>giant cargo crane</em> capable of moving crates between stacks. To ensure none of the crates get crushed or fall over, the crane operator will rearrange them in a series of carefully-planned steps. After the crates are rearranged, the desired crates will be at the top of each stack.</p>
 100 <p>The Elves don't want to interrupt the crane operator during this delicate procedure, but they forgot to ask her <em>which</em> crate will end up where, and they want to be ready to unload them as soon as possible so they can embark.</p>
 101 <p>They do, however, have a drawing of the starting stacks of crates <em>and</em> the rearrangement procedure (your puzzle input). For example:</p>
 102 <pre><code>    [D]
 103 [N] [C]
 104 [Z] [M] [P]
 105  1   2   3
 106
 107 move 1 from 2 to 1
 108 move 3 from 1 to 3
 109 move 2 from 2 to 1
 110 move 1 from 1 to 2
 111 </code></pre>
 112 <p>In this example, there are three stacks of crates. Stack 1 contains two crates: crate <code>Z</code> is on the bottom, and crate <code>N</code> is on top. Stack 2 contains three crates; from bottom to top, they are crates <code>M</code>, <code>C</code>, and <code>D</code>. Finally, stack 3 contains a single crate, <code>P</code>.</p>
 113 <p>Then, the rearrangement procedure is given. In each step of the procedure, a quantity of crates is moved from one stack to a different stack. In the first step of the above rearrangement procedure, one crate is moved from stack 2 to stack 1, resulting in this configuration:</p>
 114 <pre><code>[D]
 115 [N] [C]
 116 [Z] [M] [P]
 117  1   2   3
 118 </code></pre>
 119 <p>In the second step, three crates are moved from stack 1 to stack 3. Crates are moved <em>one at a time</em>, so the first crate to be moved (<code>D</code>) ends up below the second and third crates:</p>
 120 <pre><code>        [Z]
 121         [N]
 122     [C] [D]
 123     [M] [P]
 124  1   2   3
 125 </code></pre>
 126 <p>Then, both crates are moved from stack 2 to stack 1. Again, because crates are moved <em>one at a time</em>, crate <code>C</code> ends up below crate <code>M</code>:</p>
 127 <pre><code>        [Z]
 128         [N]
 129 [M]     [D]
 130 [C]     [P]
 131  1   2   3
 132 </code></pre>
 133 <p>Finally, one crate is moved from stack 1 to stack 2:</p>
 134 <pre><code>        [<em>Z</em>]
 135         [N]
 136         [D]
 137 [<em>C</em>] [<em>M</em>] [P]
 138  1   2   3
 139 </code></pre>
 140 <p>The Elves just need to know <em>which crate will end up on top of each stack</em>; in this example, the top crates are <code>C</code> in stack 1, <code>M</code> in stack 2, and <code>Z</code> in stack 3, so you should combine these together and give the Elves the message <code><em>CMZ</em></code>.</p>
 141 <p><em>After the rearrangement procedure completes, what crate ends up on top of each stack?</em></p>
 142 </article>
 143 <p>Your puzzle answer was <code>TGWSMRBPN</code>.</p><article class="day-desc"><h2 id="part2">--- Part Two ---</h2><p>As you watch the crane operator expertly rearrange the crates, you notice the process isn't following your prediction.</p>
 144 <p>Some mud was covering the writing on the side of the crane, and you quickly wipe it away. The crane isn't a CrateMover 9000 - it's a <em><span title="It's way better than the old CrateMover 1006.">CrateMover 9001</span></em>.</p>
 145 <p>The CrateMover 9001 is notable for many new and exciting features: air conditioning, leather seats, an extra cup holder, and <em>the ability to pick up and move multiple crates at once</em>.</p>
 146 <p>Again considering the example above, the crates begin in the same configuration:</p>
 147 <pre><code>    [D]
 148 [N] [C]
 149 [Z] [M] [P]
 150  1   2   3
 151 </code></pre>
 152 <p>Moving a single crate from stack 2 to stack 1 behaves the same as before:</p>
 153 <pre><code>[D]
 154 [N] [C]
 155 [Z] [M] [P]
 156  1   2   3
 157 </code></pre>
 158 <p>However, the action of moving three crates from stack 1 to stack 3 means that those three moved crates <em>stay in the same order</em>, resulting in this new configuration:</p>
 159 <pre><code>        [D]
 160         [N]
 161     [C] [Z]
 162     [M] [P]
 163  1   2   3
 164 </code></pre>
 165 <p>Next, as both crates are moved from stack 2 to stack 1, they <em>retain their order</em> as well:</p>
 166 <pre><code>        [D]
 167         [N]
 168 [C]     [Z]
 169 [M]     [P]
 170  1   2   3
 171 </code></pre>
 172 <p>Finally, a single crate is still moved from stack 1 to stack 2, but now it's crate <code>C</code> that gets moved:</p>
 173 <pre><code>        [<em>D</em>]
 174         [N]
 175         [Z]
 176 [<em>M</em>] [<em>C</em>] [P]
 177  1   2   3
 178 </code></pre>
 179 <p>In this example, the CrateMover 9001 has put the crates in a totally different order: <code><em>MCD</em></code>.</p>
 180 <p>Before the rearrangement process finishes, update your simulation so that the Elves know where they should stand to be ready to unload the final supplies. <em>After the rearrangement procedure completes, what crate ends up on top of each stack?</em></p>
 181 </article>
 182 <p>Your puzzle answer was <code>TZLTLWRNF</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
 183 <p>At this point, you should <a href="/2022">return to your Advent calendar</a> and try another puzzle.</p>
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