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+Advent of Code
+
+--- Day 19: Linen Layout ---
+
+   Today, The Historians take you up to the [16]hot springs on Gear Island!
+   Very [17]suspiciously, absolutely nothing goes wrong as they begin their
+   careful search of the vast field of helixes.
+
+   Could this finally be your chance to visit the [18]onsen next door? Only
+   one way to find out.
+
+   After a brief conversation with the reception staff at the onsen front
+   desk, you discover that you don't have the right kind of money to pay the
+   admission fee. However, before you can leave, the staff get your
+   attention. Apparently, they've heard about how you helped at the hot
+   springs, and they're willing to make a deal: if you can simply help them
+   arrange their towels, they'll let you in for free!
+
+   Every towel at this onsen is marked with a pattern of colored stripes.
+   There are only a few patterns, but for any particular pattern, the staff
+   can get you as many towels with that pattern as you need. Each stripe can
+   be white (w), blue (u), black (b), red (r), or green (g). So, a towel with
+   the pattern ggr would have a green stripe, a green stripe, and then a red
+   stripe, in that order. (You can't reverse a pattern by flipping a towel
+   upside-down, as that would cause the onsen logo to face the wrong way.)
+
+   The Official Onsen Branding Expert has produced a list of designs - each a
+   long sequence of stripe colors - that they would like to be able to
+   display. You can use any towels you want, but all of the towels' stripes
+   must exactly match the desired design. So, to display the design rgrgr,
+   you could use two rg towels and then an r towel, an rgr towel and then a
+   gr towel, or even a single massive rgrgr towel (assuming such towel
+   patterns were actually available).
+
+   To start, collect together all of the available towel patterns and the
+   list of desired designs (your puzzle input). For example:
+
+ r, wr, b, g, bwu, rb, gb, br
+
+ brwrr
+ bggr
+ gbbr
+ rrbgbr
+ ubwu
+ bwurrg
+ brgr
+ bbrgwb
+
+   The first line indicates the available towel patterns; in this example,
+   the onsen has unlimited towels with a single red stripe (r), unlimited
+   towels with a white stripe and then a red stripe (wr), and so on.
+
+   After the blank line, the remaining lines each describe a design the onsen
+   would like to be able to display. In this example, the first design
+   (brwrr) indicates that the onsen would like to be able to display a black
+   stripe, a red stripe, a white stripe, and then two red stripes, in that
+   order.
+
+   Not all designs will be possible with the available towels. In the above
+   example, the designs are possible or impossible as follows:
+
+     • brwrr can be made with a br towel, then a wr towel, and then finally
+       an r towel.
+     • bggr can be made with a b towel, two g towels, and then an r towel.
+     • gbbr can be made with a gb towel and then a br towel.
+     • rrbgbr can be made with r, rb, g, and br.
+     • ubwu is impossible.
+     • bwurrg can be made with bwu, r, r, and g.
+     • brgr can be made with br, g, and r.
+     • bbrgwb is impossible.
+
+   In this example, 6 of the eight designs are possible with the available
+   towel patterns.
+
+   To get into the onsen as soon as possible, consult your list of towel
+   patterns and desired designs carefully. How many designs are possible?
+
+   Your puzzle answer was 311.
+
+--- Part Two ---
+
+   The staff don't really like some of the towel arrangements you came up
+   with. To avoid an endless cycle of towel rearrangement, maybe you should
+   just give them every possible option.
+
+   Here are all of the different ways the above example's designs can be
+   made:
+
+   brwrr can be made in two different ways: b, r, wr, r or br, wr, r.
+
+   bggr can only be made with b, g, g, and r.
+
+   gbbr can be made 4 different ways:
+
+     • g, b, b, r
+     • g, b, br
+     • gb, b, r
+     • gb, br
+
+   rrbgbr can be made 6 different ways:
+
+     • r, r, b, g, b, r
+     • r, r, b, g, br
+     • r, r, b, gb, r
+     • r, rb, g, b, r
+     • r, rb, g, br
+     • r, rb, gb, r
+
+   bwurrg can only be made with bwu, r, r, and g.
+
+   brgr can be made in two different ways: b, r, g, r or br, g, r.
+
+   ubwu and bbrgwb are still impossible.
+
+   Adding up all of the ways the towels in this example could be arranged
+   into the desired designs yields 16 (2 + 1 + 4 + 6 + 1 + 2).
+
+   They'll let you into the onsen as soon as you have the list. What do you
+   get if you add up the number of different ways you could make each design?
+
+   Your puzzle answer was 616234236468263.
+
+   Both parts of this puzzle are complete! They provide two gold stars: **
+
+   At this point, you should [19]return to your Advent calendar and try
+   another puzzle.
+
+   If you still want to see it, you can [20]get your puzzle input.
+
+References
+
+   Visible links
+   1. https://adventofcode.com/
+   2. https://adventofcode.com/2024/about
+   3. https://adventofcode.com/2024/events
+   4. https://cottonbureau.com/people/advent-of-code
+   5. https://adventofcode.com/2024/settings
+   6. https://adventofcode.com/2024/auth/logout
+   7. Advent of Code Supporter
+	https://adventofcode.com/2024/support
+   8. https://adventofcode.com/2024
+   9. https://adventofcode.com/2024
+  10. https://adventofcode.com/2024/support
+  11. https://adventofcode.com/2024/sponsors
+  12. https://adventofcode.com/2024/leaderboard
+  13. https://adventofcode.com/2024/stats
+  16. https://adventofcode.com/2023/day/12
+  17. https://www.youtube.com/watch?v=ekL881PJMjI
+  18. https://en.wikipedia.org/wiki/Onsen
+  19. https://adventofcode.com/2024
+  20. https://adventofcode.com/2024/day/19/input