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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">22*</span></div></div><div><h1 class="title-event">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="title-event-wrap">/*</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 11: Monkey in the Middle ---</h2><p>As you finally start making your way upriver, you realize your pack is much lighter than you remember. Just then, one of the items from your pack goes flying overhead. Monkeys are playing <a href="https://en.wikipedia.org/wiki/Keep_away" target="_blank">Keep Away</a> with your missing things!</p>
99 <p>To get your stuff back, you need to be able to predict where the monkeys will throw your items. After some careful observation, you realize the monkeys operate based on <em>how worried you are about each item</em>.</p>
100 <p>You take some notes (your puzzle input) on the items each monkey currently has, how worried you are about those items, and how the monkey makes decisions based on your worry level. For example:</p>
101 <pre><code>Monkey 0:
102 Starting items: 79, 98
103 Operation: new = old * 19
104 Test: divisible by 23
105 If true: throw to monkey 2
106 If false: throw to monkey 3
107
108 Monkey 1:
109 Starting items: 54, 65, 75, 74
110 Operation: new = old + 6
111 Test: divisible by 19
112 If true: throw to monkey 2
113 If false: throw to monkey 0
114
115 Monkey 2:
116 Starting items: 79, 60, 97
117 Operation: new = old * old
118 Test: divisible by 13
119 If true: throw to monkey 1
120 If false: throw to monkey 3
121
122 Monkey 3:
123 Starting items: 74
124 Operation: new = old + 3
125 Test: divisible by 17
126 If true: throw to monkey 0
127 If false: throw to monkey 1
128 </code></pre>
129 <p>Each monkey has several attributes:</p>
130 <ul>
131 <li><code>Starting items</code> lists your <em>worry level</em> for each item the monkey is currently holding in the order they will be inspected.</li>
132 <li><code>Operation</code> shows how your worry level changes as that monkey inspects an item. (An operation like <code>new = old * 5</code> means that your worry level after the monkey inspected the item is five times whatever your worry level was before inspection.)</li>
133 <li><code>Test</code> shows how the monkey uses your worry level to decide where to throw an item next.
134 <ul>
135 <li><code>If true</code> shows what happens with an item if the <code>Test</code> was true.</li>
136 <li><code>If false</code> shows what happens with an item if the <code>Test</code> was false.</li>
137 </ul>
138 </li>
139 </ul>
140 <p>After each monkey inspects an item but before it tests your worry level, your relief that the monkey's inspection didn't damage the item causes your worry level to be <em>divided by three</em> and rounded down to the nearest integer.</p>
141 <p>The monkeys take turns inspecting and throwing items. On a single monkey's <em>turn</em>, it inspects and throws all of the items it is holding one at a time and in the order listed. Monkey <code>0</code> goes first, then monkey <code>1</code>, and so on until each monkey has had one turn. The process of each monkey taking a single turn is called a <em>round</em>.</p>
142 <p>When a monkey throws an item to another monkey, the item goes on the <em>end</em> of the recipient monkey's list. A monkey that starts a round with no items could end up inspecting and throwing many items by the time its turn comes around. If a monkey is holding no items at the start of its turn, its turn ends.</p>
143 <p>In the above example, the first round proceeds as follows:</p>
144 <pre><code>Monkey 0:
145 Monkey inspects an item with a worry level of 79.
146 Worry level is multiplied by 19 to 1501.
147 Monkey gets bored with item. Worry level is divided by 3 to 500.
148 Current worry level is not divisible by 23.
149 Item with worry level 500 is thrown to monkey 3.
150 Monkey inspects an item with a worry level of 98.
151 Worry level is multiplied by 19 to 1862.
152 Monkey gets bored with item. Worry level is divided by 3 to 620.
153 Current worry level is not divisible by 23.
154 Item with worry level 620 is thrown to monkey 3.
155 Monkey 1:
156 Monkey inspects an item with a worry level of 54.
157 Worry level increases by 6 to 60.
158 Monkey gets bored with item. Worry level is divided by 3 to 20.
159 Current worry level is not divisible by 19.
160 Item with worry level 20 is thrown to monkey 0.
161 Monkey inspects an item with a worry level of 65.
162 Worry level increases by 6 to 71.
163 Monkey gets bored with item. Worry level is divided by 3 to 23.
164 Current worry level is not divisible by 19.
165 Item with worry level 23 is thrown to monkey 0.
166 Monkey inspects an item with a worry level of 75.
167 Worry level increases by 6 to 81.
168 Monkey gets bored with item. Worry level is divided by 3 to 27.
169 Current worry level is not divisible by 19.
170 Item with worry level 27 is thrown to monkey 0.
171 Monkey inspects an item with a worry level of 74.
172 Worry level increases by 6 to 80.
173 Monkey gets bored with item. Worry level is divided by 3 to 26.
174 Current worry level is not divisible by 19.
175 Item with worry level 26 is thrown to monkey 0.
176 Monkey 2:
177 Monkey inspects an item with a worry level of 79.
178 Worry level is multiplied by itself to 6241.
179 Monkey gets bored with item. Worry level is divided by 3 to 2080.
180 Current worry level is divisible by 13.
181 Item with worry level 2080 is thrown to monkey 1.
182 Monkey inspects an item with a worry level of 60.
183 Worry level is multiplied by itself to 3600.
184 Monkey gets bored with item. Worry level is divided by 3 to 1200.
185 Current worry level is not divisible by 13.
186 Item with worry level 1200 is thrown to monkey 3.
187 Monkey inspects an item with a worry level of 97.
188 Worry level is multiplied by itself to 9409.
189 Monkey gets bored with item. Worry level is divided by 3 to 3136.
190 Current worry level is not divisible by 13.
191 Item with worry level 3136 is thrown to monkey 3.
192 Monkey 3:
193 Monkey inspects an item with a worry level of 74.
194 Worry level increases by 3 to 77.
195 Monkey gets bored with item. Worry level is divided by 3 to 25.
196 Current worry level is not divisible by 17.
197 Item with worry level 25 is thrown to monkey 1.
198 Monkey inspects an item with a worry level of 500.
199 Worry level increases by 3 to 503.
200 Monkey gets bored with item. Worry level is divided by 3 to 167.
201 Current worry level is not divisible by 17.
202 Item with worry level 167 is thrown to monkey 1.
203 Monkey inspects an item with a worry level of 620.
204 Worry level increases by 3 to 623.
205 Monkey gets bored with item. Worry level is divided by 3 to 207.
206 Current worry level is not divisible by 17.
207 Item with worry level 207 is thrown to monkey 1.
208 Monkey inspects an item with a worry level of 1200.
209 Worry level increases by 3 to 1203.
210 Monkey gets bored with item. Worry level is divided by 3 to 401.
211 Current worry level is not divisible by 17.
212 Item with worry level 401 is thrown to monkey 1.
213 Monkey inspects an item with a worry level of 3136.
214 Worry level increases by 3 to 3139.
215 Monkey gets bored with item. Worry level is divided by 3 to 1046.
216 Current worry level is not divisible by 17.
217 Item with worry level 1046 is thrown to monkey 1.
218 </code></pre>
219 <p>After round 1, the monkeys are holding items with these worry levels:</p>
220 <pre><code>Monkey 0: 20, 23, 27, 26
221 Monkey 1: 2080, 25, 167, 207, 401, 1046
222 Monkey 2:
223 Monkey 3:
224 </code></pre>
225 <p>Monkeys 2 and 3 aren't holding any items at the end of the round; they both inspected items during the round and threw them all before the round ended.</p>
226 <p>This process continues for a few more rounds:</p>
227 <pre><code>After round 2, the monkeys are holding items with these worry levels:
228 Monkey 0: 695, 10, 71, 135, 350
229 Monkey 1: 43, 49, 58, 55, 362
230 Monkey 2:
231 Monkey 3:
232
233 After round 3, the monkeys are holding items with these worry levels:
234 Monkey 0: 16, 18, 21, 20, 122
235 Monkey 1: 1468, 22, 150, 286, 739
236 Monkey 2:
237 Monkey 3:
238
239 After round 4, the monkeys are holding items with these worry levels:
240 Monkey 0: 491, 9, 52, 97, 248, 34
241 Monkey 1: 39, 45, 43, 258
242 Monkey 2:
243 Monkey 3:
244
245 After round 5, the monkeys are holding items with these worry levels:
246 Monkey 0: 15, 17, 16, 88, 1037
247 Monkey 1: 20, 110, 205, 524, 72
248 Monkey 2:
249 Monkey 3:
250
251 After round 6, the monkeys are holding items with these worry levels:
252 Monkey 0: 8, 70, 176, 26, 34
253 Monkey 1: 481, 32, 36, 186, 2190
254 Monkey 2:
255 Monkey 3:
256
257 After round 7, the monkeys are holding items with these worry levels:
258 Monkey 0: 162, 12, 14, 64, 732, 17
259 Monkey 1: 148, 372, 55, 72
260 Monkey 2:
261 Monkey 3:
262
263 After round 8, the monkeys are holding items with these worry levels:
264 Monkey 0: 51, 126, 20, 26, 136
265 Monkey 1: 343, 26, 30, 1546, 36
266 Monkey 2:
267 Monkey 3:
268
269 After round 9, the monkeys are holding items with these worry levels:
270 Monkey 0: 116, 10, 12, 517, 14
271 Monkey 1: 108, 267, 43, 55, 288
272 Monkey 2:
273 Monkey 3:
274
275 After round 10, the monkeys are holding items with these worry levels:
276 Monkey 0: 91, 16, 20, 98
277 Monkey 1: 481, 245, 22, 26, 1092, 30
278 Monkey 2:
279 Monkey 3:
280
281 ...
282
283 After round 15, the monkeys are holding items with these worry levels:
284 Monkey 0: 83, 44, 8, 184, 9, 20, 26, 102
285 Monkey 1: 110, 36
286 Monkey 2:
287 Monkey 3:
288
289 ...
290
291 After round 20, the monkeys are holding items with these worry levels:
292 Monkey 0: 10, 12, 14, 26, 34
293 Monkey 1: 245, 93, 53, 199, 115
294 Monkey 2:
295 Monkey 3:
296 </code></pre>
297 <p>Chasing all of the monkeys at once is impossible; you're going to have to focus on the <em>two most active</em> monkeys if you want any hope of getting your stuff back. Count the <em>total number of times each monkey inspects items</em> over 20 rounds:</p>
298 <pre><code><em>Monkey 0 inspected items 101 times.</em>
299 Monkey 1 inspected items 95 times.
300 Monkey 2 inspected items 7 times.
301 <em>Monkey 3 inspected items 105 times.</em>
302 </code></pre>
303 <p>In this example, the two most active monkeys inspected items 101 and 105 times. The level of <em>monkey business</em> in this situation can be found by multiplying these together: <code><em>10605</em></code>.</p>
304 <p>Figure out which monkeys to chase by counting how many items they inspect over 20 rounds. <em>What is the level of monkey business after 20 rounds of stuff-slinging simian shenanigans?</em></p>
305 </article>
306 <p>Your puzzle answer was <code>112815</code>.</p><article class="day-desc"><h2 id="part2">--- Part Two ---</h2><p>You're worried you might not ever get your items back. So worried, in fact, that your relief that a monkey's inspection didn't damage an item <em>no longer causes your worry level to be divided by three</em>.</p>
307 <p>Unfortunately, that relief was all that was keeping your worry levels from reaching <em>ridiculous levels</em>. You'll need to <em>find another way to keep your worry levels manageable</em>.</p>
308 <p>At this rate, you might be putting up with these monkeys for a <em>very long time</em> - possibly <em><code>10000</code> rounds</em>!</p>
309 <p>With these new rules, you can still figure out the <span title="Monkey business monkey business monkey business, monkey numbers... is this working?">monkey business</span> after 10000 rounds. Using the same example above:</p>
310 <pre><code>== After round 1 ==
311 Monkey 0 inspected items 2 times.
312 Monkey 1 inspected items 4 times.
313 Monkey 2 inspected items 3 times.
314 Monkey 3 inspected items 6 times.
315
316 == After round 20 ==
317 Monkey 0 inspected items 99 times.
318 Monkey 1 inspected items 97 times.
319 Monkey 2 inspected items 8 times.
320 Monkey 3 inspected items 103 times.
321
322 == After round 1000 ==
323 Monkey 0 inspected items 5204 times.
324 Monkey 1 inspected items 4792 times.
325 Monkey 2 inspected items 199 times.
326 Monkey 3 inspected items 5192 times.
327
328 == After round 2000 ==
329 Monkey 0 inspected items 10419 times.
330 Monkey 1 inspected items 9577 times.
331 Monkey 2 inspected items 392 times.
332 Monkey 3 inspected items 10391 times.
333
334 == After round 3000 ==
335 Monkey 0 inspected items 15638 times.
336 Monkey 1 inspected items 14358 times.
337 Monkey 2 inspected items 587 times.
338 Monkey 3 inspected items 15593 times.
339
340 == After round 4000 ==
341 Monkey 0 inspected items 20858 times.
342 Monkey 1 inspected items 19138 times.
343 Monkey 2 inspected items 780 times.
344 Monkey 3 inspected items 20797 times.
345
346 == After round 5000 ==
347 Monkey 0 inspected items 26075 times.
348 Monkey 1 inspected items 23921 times.
349 Monkey 2 inspected items 974 times.
350 Monkey 3 inspected items 26000 times.
351
352 == After round 6000 ==
353 Monkey 0 inspected items 31294 times.
354 Monkey 1 inspected items 28702 times.
355 Monkey 2 inspected items 1165 times.
356 Monkey 3 inspected items 31204 times.
357
358 == After round 7000 ==
359 Monkey 0 inspected items 36508 times.
360 Monkey 1 inspected items 33488 times.
361 Monkey 2 inspected items 1360 times.
362 Monkey 3 inspected items 36400 times.
363
364 == After round 8000 ==
365 Monkey 0 inspected items 41728 times.
366 Monkey 1 inspected items 38268 times.
367 Monkey 2 inspected items 1553 times.
368 Monkey 3 inspected items 41606 times.
369
370 == After round 9000 ==
371 Monkey 0 inspected items 46945 times.
372 Monkey 1 inspected items 43051 times.
373 Monkey 2 inspected items 1746 times.
374 Monkey 3 inspected items 46807 times.
375
376 == After round 10000 ==
377 <em>Monkey 0 inspected items 52166 times.</em>
378 Monkey 1 inspected items 47830 times.
379 Monkey 2 inspected items 1938 times.
380 <em>Monkey 3 inspected items 52013 times.</em>
381 </code></pre>
382 <p>After 10000 rounds, the two most active monkeys inspected items 52166 and 52013 times. Multiplying these together, the level of <em>monkey business</em> in this situation is now <code><em>2713310158</em></code>.</p>
383 <p>Worry levels are no longer divided by three after each item is inspected; you'll need to find another way to keep your worry levels manageable. Starting again from the initial state in your puzzle input, <em>what is the level of monkey business after 10000 rounds?</em></p>
384 </article>
385 <p>Your puzzle answer was <code>25738411485</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
386 <p>At this point, you should <a href="/2022">return to your Advent calendar</a> and try another puzzle.</p>
387 <p>If you still want to see it, you can <a href="11/input" target="_blank">get your puzzle input</a>.</p>
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